BIO 2 FINAL

Mammal Type: Placental (Eutheria)

(18 orders - dominant mammals on earth!) Placental mammals - Prolonged gestation - Embryo in uterus supplied with nutrients from placenta - Extended care from parents - Young mammals have inborn capacity to learn

Aves (reptilia)

- birds - evolved from reptiles - now considered part of reptiles - EVOLUTION: Theropod dinosaurs -> archaeopteryx -> 27 modern bird orders (2 major groups): RATITES AND CARINATES - tremendous uniformity of structure unlike other reptile groups *feathers = single unifying feature. - if it has feathers it is a bird* - lay eggs with hard, calcified shells - scales on legs claws on toes horny beaks

Jawless fishes = Agnathans = Lampreys

- (filter-feeders or parasites) - decimated trout populations in Great Lakes - cylindrical body, no fins - smooth nonscaly skin.

Rotifera - mastax, trophi, corona, parthenogenesis

- 2,200 species - Named for crown of cilia resembling a rotating wheel (CORONA) - where the cilia beat to bring the food to the mouth and move the animal through the water column - Serves as both an organ of locomotion and aids direction of food to mouth - MASTAX = pharynx - TROPHI = chitinous jaws for grinding - Abundant in freshwater - Pseudocoelomate - Complete digestive system - mouth at one end, anus at the other - Salivary glands, digestive glands - Ladder-type nervous system - Engage in unique reproduction: - PARTHENOGENESIS: Allows female population to grow and produce clones - large female populations - to take advantage favorable conditions - don't have to waste time/resources finding a mate

Vertebrates

- 4 chordate characteristics - notochord replaced by vertebral column which surrounds dorsal nerve cord - strong flexible endoskeleton (cartilage or bone) - many with paired appendages - skull encases brain - high degree of cephalization - well-developed senses - complete digestive system - large coelom - closed circulation - chambered heart - gill or lungs for gas exchange - kidneys excrete nitrogenous wastes - sexual reproduction

Phylum Nematoda - Pseudocoelomate, hydrostatic skeleton, cuticle, longitudinal muscles, eutely, roundworms, hookworms, Guinea worm, Trichina worms, Filarial worms

- A CUTICLE provides support and protection - HYDROSTATIC SKELETON: body wall is held rigid by pressure from the interior organs - HOOKWORM: - As adults, hook worms attach themselves to your intestinal lining - they feed on your blood - the more you have, the more likely you are to experience iron-deficiency anemia - intestine starts bleeding - Leading cause of maternal and child morbidity worldwide - ROUNDWORM: - Non-segmented, generally colorless worms - Larger ones - PSUEDOCOELOMATE (body cavity not derived from mesoderm) - Parasitic roundworms infect humans, animals, plants - Homogeneous morphology - Molt cuticle - EUTELY - bodies are built out of a species-specific number of cells - consequence - once body gets to that number of cells, their cells lose their ability to divide and start aging - Only LONGITUDINAL muscles - GUINEA WORM: Dracunculus medinensis (transmitted by copepod in drinking water - human host - produces ulceration on skin where eggs are released when human is in water - removed by twirling on a stick) - TRICHINA WORM: Trichinella spiralis (ingestion of infected muscle; occasional in humans) - FILARIAL WORM: Wuchereria bancrofti and Brugia malayi (transmitted by mosquitoes; elephantiasis; worms reside in lymphatic system leading to swelling of affected parts)

Phylum Arthropoda - Eucoelomate, protostomes, metamerism, tagamata, exoskeleton, chitin, jointed appendages, hemocoel, tracheae, spiracles, Malpighian tubules

- Arthropods have freely moveable JOINTED APPENDAGES - Very successful due to many characteristics - Rigid, jointed EXOSKELETON - CHITIN - Must molt as they grow - HOMECOEL: body cavity that provides a rigid framework and stretches opposing muscles - Antagonistic pairs: opposing muscle contraction (i.e. flexion and extension) - Segmented, fused (TAGAMATA) - Head(feeding and gaining info), thorax(movement), abdomen - Tagmosis: fused body segments forming functional regions - Setae - sensory hairs that run through exoskeleton and tie in to animal's nervous system - Extensive cephalization - excretion: MALPIGHIAN TUBULES system is a type of excretory and osmoregulatory system - breathe through SPIRACLES, gas exchange through network of tubules called TRACHEAE - METAMERISM is the repetition of homologous body segments - seen in annelids + more advanced in arthropods

Bird Anatomy (form -> function)

- CARINATE: - Flighted bc they have keeled sternum and strong pectorals - Fore limbs for flying, hind limbs for swimming and walking ~9,900+ species - RATITE: -Flightless bc they have flat sternum and weak pectorals - Run to escape predators ~40 species - WINGS: 1. ELLIPTICAL wings: - Large wing slits, broad, elliptical surface - High maneuverability - Requires constant flapping - *for birds that fly in and out of trees in the forest - well suited to moving quickly among trees* 2. SOARING wings: - Long, narrow wings - Fly without flapping by exploiting ocean currents - High aspect ratio - long and narrow - Most efficient of the wings - require least amount of energy to engage in flight - *characteristic of birds that fly long distances over the ocean* 3. HIGH-SPEED wings: - Swept back to slender tip - Fast flight; sustained speeds - Allow hummingbirds to hover and to fly backwards - * i.e. swallows, hummingbirds, plover, gulls, terns 4. HIGH-LIFT wings: - Long, broad wing, high lift at low speeds - Land soarers - Predators with heavy loads - swoop down, catch prey, then fly off - I.e. eagles, hawks, owls - hollow - light bones (pneumatized) - FEATHERS: - Feathers are epidermally derived, made of keratin - They are modified scales: epithelial placodes (scales, feathers, hair) - Molt 1 time / year, replaceable - Varieties of feather: - Soft/downy - feathers to maintain heat - Contour - stiff, airfoil shape to generate lift (most abundant) - Preening - process of cleaning feathers that mates do - extensive respiratory air sacs: very efficient breathing - Air is moved across the lungs in both inhalation and exhalation - takes 2 complete respiratory cycles to use the air - allows maximum oxygenation of blood - Sensitive to airborne toxins - Vocalizations are important means of communication - genetically encoded songs - Reduction of organs - only one ovary, no urinary bladder, no teeth (enhances flight by reducing weight) - high metabolic rate - 4 chambered heart - fast heart rate - double-loop circulation

Mammal type: Marsupials (Metatheria)

- born immature, newborns crawl into pouch and attach to nipples for extended time - Australia, S. America - Pouched mammals - Primitive yolk sac - Short gestation - Tiny, blind, hairless young - Suckled in pouch - Embryonic diapause (delayed implantation - embryo can sit and wait) - embryo can be in reproductive tract while joey is still in pouch - increases population in short order - Prolonged period of lactation and parental care

Cectodes (Tapeworms) - scolex, germinative zone (neck), strobila, proglottids, life cycle (beef and pork) hydatid cyst - Echinococcus sp.

- Cestodes: (TAPEWORMS) - parasitic flatworms: - Have anterior region with modifications for attachment to intestinal wall of host (SCOLEX) - Body (STROBILA) - long series of PROGLOTTIDS containing ovaries and tesits - begin to develop in GERMINATIVE ZONE at the neck of tapeworm to produce larvae - Self-fertilize - Complicated life cycles - Each segment contains a full set of male and female sex organs - LIFE CYCLE (pork/beef): - pork = Taenia solium - beef = Taenia saginata - primary/definitive host (human) ingests meat containing bladder worms - bladder worm attaches to human intestine where it matures into tapeworm - as tape worm grows, proglottis produces eggs that leave primary host in feces which can contaminate water or vegetation - livestock may ingest eggs, becoming secondary host as each larva becomes a bladder worm - rare or uncooked meat from secondary host contains many bladder worms - cycle repeats. - ECHINOCOCCUS GRANULOSUS = HYDATID cysts of juveniles in humans - infection by contact with dogs and ruminants

Bivalves: mussels, clams, scallops, oysters, filter feeders, siphon, shell, hinge ligament, adductor mussels, byssal threads, gills, trochophore, veliger

- Clams, oysters, mussels, scallops Body is encased in a 2-part shell held closed by ADDUCTOR muscles - No head, no RADULA - Operate largely as FILTER FEEDERS - very successful at capturing food particles suspended in water column - huge GILLS - Ciliated gills hang down within mantle cavity on either side of visceral mass - Gills operate on COUNTERCURRENT EXCHANGE; water flowing in one direction over the gill surface - blood flows within the gills in the opposite direction - allows maximum oxygenation of the blood because it always in contact with oxygen-rich water - Circulatory system is open - Sexes are separate - Beating of cilia causes water to enter cavity - capture tiny food particles the VELIGER - free-swimming larva of many molluscs, having a rudimentary shell and a ciliated velum used for feeding and locomotion - develops from the TROCHOPHORE (larvae) - BYSSAL THREADS anchor mussels onto rocks

Corals - zooxanthellae, calcareous cup, mutualism, reefs; Ocean Acidification

- Coral REEFS - Hermatypic corals - reef building corals (ahermatypic corals do not build reefs) - Tiny polyps that secrete their own CALCAREOUS CUPS by pulling calcium carbonate out of the water column - Polyps all connected by common gut - Symbiotic association with ZOOXANTHELLAE - They tend to grow slowly - live in nutrient deprived waters - survive off of nutrients provided by zooxanthellae that are packing them - Zooxanthellae rely on carbon dioxide given off by corals to run photosynthesis and survive - MUTUALISTIC relationship: zooxanthellae (primary producers) get nice place to live and carbon dioxide waste products from corals - corals get nutrients they need to survive from zooxanthellae - Corals cannot grow where they do not have zooxanthellae - OCEAN ACIDIFICATION: - Rise in hydrogen ions due to excess CO2 in the atmosphere causing pH to increase - decreases ability of corals to take calcium carbonate from the water column and grow their reefs - Bleaching = loss of zooxanthellae = death of coral - Great Barrier reef - 5 mass bleaching events since 1998

Echinodermata - Deuterostomes, spiny skin, radial, pentamerous symmetry, endoskeleton, water-vascular system, tube feet, pedicellariae, dermal branchiae, ambulacral grooves, cardiac stomach, gastric (pyloric) stomach, digestive ceca, metamorphosis

- DEUTEROSTOMES: - echinoderms and chordates - cleavage = radial, indeterminate - blastopore becomes anus - eucoelomate - entercoely - WATER VASCULAR SYSTEM: madreporite stone canal ring canal 5 radial canals lateral canals ampulla tube foot - spiny skin, radial symmetry as adults, pentamerous (multiples of 5) symmetry, endoskeleton - PEDICELLARIAE = a defensive organ like a minute pincer present in large number - DERMAL BRANCHIAE = projections of the coelom that serve in waste removal and respiration - AMBULACRAL GROOVES = oral surface from which TUBE FEET project (movement, feeding, respiration) - The upper part is called the PYLORIC stomach and the lower part is called the CARDIAC stomach - DIGESTIVE CECA - produce digestive enzymes - METAMORPHOSIS: Eggs hatch into free-swimming larvae. The larvae undergo metamorphosis to change into the adult form

Bird features

- ENDOTHERMIC: ability to maintain constant body temperature without relying on outside heat sources like the sun - well-developed sense organs and nervous system - social - altricial and precocial young: PRECOCIAL: - Covered with down - Active young - Run and swim as soon as they are dry after hatching i.e. quail, ducks, geese, fowl, water birds - Capable of getting own food resources after drying off ALTRICIAL: - Naked and helpless - In nest for 1+ week - Require care from parents - I.e. perching birds, raptors, songbirds, penguins - cannot go out and find their own food - will die if parents abandon nest

Cephalopods - nautilus, cuttlefish, squid, octopus, siphuncle, ink sac, chromatophores, cuttlebone, pen, jet propulsion, giant axons

- Head footed: GIANT AXON activates muscles of mantle, forcing water out of mantle cavity through the siphon (JET PROPULSION for movement of animal) - Tentacles and arms capture prey by adhesive secretions or suckers - Beak (made of chitin) used to tear prey apart - radula is enclosed in the beak - Well-developed sense organs - i.e. octopus has a 10-lobed brain and eyes that from images - Closed circulatory system unlike the rest of the molluscs - low fluid volume, high pressure system - Accessory "brachial" hearts sitting on top of each gill to enhance the movement of oxygen rich blood from gills to the rest of the body - Rely on direct exchange, NOT countercurrent exchange - Spermatophore - sac that is passed from males to females using modified arm called - Hectocotylus - internal fertilization - Offspring have direct development - go through trochophore and veliger stage in utero - Only cephalopod with a true external shell = the NAUTILUS - Shell arranged in a spiral - connected by cords of connective tissue called SIPHUNCLE - arranged to help maintain buoyancy (because shell is heavy) -CUTTLEFISH - type of cephalopod with chromatophores that allow animal to change color - CUTTLEBONE in cuttlefish helps them maintain buoyancy - Most animals use their CHROMATOPHORES to blend in and hide from predators -SQUID has shell called a PEN and a fin; octopus do not have a shell or fins - OCTOPUS = only invertebrate to engage in bipedal locomotion - can walk on two arms and the only invertebrate to use tools - i.e. carry coconut shell to hide in - all Coleoidea (squid, octopus and cuttlefish) which dwell in light conditions have an INK SAC, which can be used to expel a cloud of dark ink in order to confuse predators

Cnidaria: Scyphozoa (Jelly) - life cycle, scyphistoma, strobila, ephyra, Cubozoa

- Medusa; thick mesoglea 95% water - Float in open sea - swims actively up, floats passively down - Manubrium with oral lobes - Stomach with pouches - Sense organs = rhopalium (statocyst + ocelli) - Separate sexes - male and female - Egg and sperm on clover leaf shaped structure on head - Over the scope of the cnidarian life cycle, part of it is spent as a polyp and part of it is spent as a medusa - STROBILATION - sexual budding - like stacking of plates (STROBILA) - all resulting organisms are clones - genetically identical - The process by which new medusae are produced is called 'strobilation' and involves metamorphosis of the end of a SCHYPHISTOMA into an EPHYRA, an immature medusa, that subsequently detaches and swims away. - CUBOZOA- box jellies - Characterized by square bell - Sea wasp (Chironex fleckeri) - Don't swim passively - very good swimmers - will hunt down their prey - Humans that get stung get permanent scars that turn black - dermonecrotic toxins kill your skin cells - cardiotoxins increase your heart rate, neurotoxins diminish your control over your diaphragm

Annelida - Segmented worms, Lophotrochozoans, eucoelomate, protostome, chaetae, parapodia, prostomium, peristomium, jaws, Errantia, Sedentaria, closed circulation, ventral nerve cord, trochophore, atoke, epitoke, nephridia, peristalsis

- PROTOSTOMES, LOPHOTROCHOZOANS, EUCOELOMATES (true) - CHAETAE (bristles) - made of chitin - help in movement (not Setae); important in temporary attachment - allow grip and digging, prevent backwards sliding (don't confuse with arthropods setae) - Isolated groups of opposing muscles allows for different activities to be going on within different segments of the animal = - PERISTALSIS = alternating waves of muscle contraction = how worms crawl (peristalsis occurs in humans when we swallow to propel food) - PROSTOMIUM = first body segment of worm - hairs, jaws, eyes for seeing - specialized for sensory information and feeding - Some polychaetes protect the major body parts and release the reproductive parts (eggs and sperm) in the EPITOKY, which breaks off - simultaneous release puts all the egg and sperm of the species in the water column at the same time to ensure successful reproduction - PERISTOMIUM = area around the worm's mouth - CLOSED CIRCULATORY SYSTEM - Double transport system: circulatory system and coelomic fluid both carry nutrients, wastes and respiratory gasses - Gut connects all the cells in the animal's body to each other - VENTRAL (solid) NERVE CORD - Giant axons facilitate rapid responses - allows for more and faster muscle activities - Major Annelidan Groups: - ERRANTARIA: - Long chaetae on footlike PARAPODIA - Most are free-ranging predators - Well-developed eyes, powerful jaws - Often brightly colored - Earthworms, leeches - SEDENTARIA: - Chaetae close to body wall to facilitate anchoring in burrows - Tube worms: marine, filter food from water with crown of tentacles

Cnidarians: Anthozoa (Sea anemones) - septa, siphonoglyph, pedal laceration

- Polyp; no medusa - Sea anemones, hard corals, sea fans - Large gastrovascular cavity with SEPTA; help to divide the gut - Ciliated grove - SIPHONOGLYPH; help pump water into the gut - Circular and longitudinal muscles; muscular body wall Attachment by pedal disk at their base - firmly anchored - they will swim away from predators like anemones swimming away from sea stars - PEDAL LACERATION - long threads that shoot out of the gut and paralyze their target - they are defending their space on the ocean bottom in order to ensure successful reproduction for themselves Potent nematocysts / Acontia

Ecdysozoa: Nematoda and Arthropoda

- Separation from Lophotrochozoa supported by both molecular data and morphology - Named for Ecdysis - molting - A cuticle provides support and protection - Some species undergo metamorphosis - Internal fertilization; amoeboid sperm - Formation of zygote that can be laid into capsule in dry environment - Allows colonization of dry environments - Of the 8 phyla, Nematodes and Arthropods are the most common

Gastropoda (snails, slugs, nudibranchs, etc.), torsion, fouling, univalve shell, cerata (extensions of nudibranch body with nematocyst from food), conotoxin

- Snails, slugs, nudibranchs, limpets -Have elongated, flattened foot for crawling - Well-developed head region - Eyes and tentacles project from coiled shell - Gills are found in mantle cavity in aquatic gastropods - Mantle functions as lung in terrestrial gastropods - Operculum ("trap-door") seals the body in the shell

Urochordates = tunicates, sea squirts, tunic, siphons, pharyngeal gill slits, paedomorphosis, tadpole larva

- Tunicates (SEA SQUIRTS) - Specialized sessile adults encased in TUNIC - Filter feeder (through PHARYNGEAL GILL SLITS) - Endostyle (secrets iodinated hormones) - SIPHON: a barrel-shaped sack with two openings or siphons that water passes through - Tadpole larvae - All 5 chordate characteristics present - Vertebrate ancestor (?) - PAEDOMORPHOSIS: (chordate origins) evolutionary process in which larval or juvenile features of an ancestral organism are displaced to the adult forms of its descendants

Osteichthyes - , diverse, bony skeleton ray-finned fishes - thin, bony rays supporting the fins, skin with ctenoid or cycloid scales (dermal derivatives of bone), gills covered by operculum, swim bladder, hypoosmotic regulators, hyperosmotic regulators, paired pelvic and pectoral fins, homocercal tail lobe-finned fishes - 6 species of lung fishes, 1 species of coelocanth, fleshy fins supported by bone, scuttle on land (pond to pond), breath air, related to amphibian ancestor.

- all vertebrates with a bony skeleton - largest group fo vertebrates ray-finned fishes: - thin, bony rays supporting the fins with ctenoid or cycloid scales (dermal derivatives of bone) - gills covered by operculum - swim bladder - helps maintain buoyancy - paired pelvic and pectoral fins - homocercal tail (even/symmetrical lobes) lobe-finned fishes: - 6 species of lung fishes - 1 species of coelocanth - fleshy fins supported by bone - scuttle on land (pond to pond) - breathe air related to amphibian ancestor OSMOREGULATION: - marine teleosts: hypo-osmotic regulators - Problem: lose water, gain salts - Risk for dehydration - Solution: drink seawater, excrete salts across gills - freshwater teleosts: hyper-osmotic regulators - Problem: water enters by osmosis, slat lost by diffusion - Risk of drowning - Solution: scales and mucus, water pumped across kidney; salt absorbing cells in gills Some fish migrate between the environments across their lifespan (in either direction) - they have to change their regulation to adapt - physiology has to be able to accommodate life in both environments

Fishes

- aquatic - gill-breathing. - ectothermic - vertebrates - usually have fins and skin covered with scales

Ctenophores - colloblasts, ctenes, bioluminescence, basal?

- ctenophores = radiata - comb jellies - all marine - 8 comb rows = CTENES; covered by long cilia (Ctenes glow due to light diffraction from long cone rows of cilia; Largest organisms to have ciliary locomotion; Move through the water without disturbing the water; good predators using tentacles to capture prey and good at hiding) - 2 long tentacles = COLLOBLASTS (Sticky, harpoon-like heads on long coiled up fibers/filaments - when cells are stimulated they come shooting out to entangle their prey) - no nematocysts - Apical sense organ (Brain-like device that helps them determine up from down in the water column) - hermaphroditic - BIOLUMINESCENCE: When the cilia beat, light is scattered, producing a rainbow of colors. - BASAL (earliest diverging group within a clade) - no Hox genes

Mammal type: Monotremes (Protheria)

- egg-laying mammals i.e. anteater, platypus Prototheria: monotremes (1 order) Egg-laying mammals No pregnancy

Tetrapods - Reptilia

- evolved from amphibian ancestor; first truly terrestrial vertebrates - internal fertilization (Female inserts embryo into egg after internal sexual fertilization) - copulatory organ - shelled - amniotic egg (desiccation-resistant egg: egg that resists drying out) *Amniotic egg broke tie to water* - Amnion: protects embryo in fluid-filled sac - provides it with food + fluid - Yolk sac: encloses reserve of nutrients - gets smaller as embryo grows - Allantois: contains wastes from embryo - gets larger as embryo grows - Chorion: allows gas exchange (with allantois) All four structures are encased by the egg shell - Shell is permeable to O2 and CO2 (Both types of shell permit gas exchange): - Reptiles: shell is soft and leathery Birds: shell is hard and calcareous - thoracic breathing - negative pressure - muscles expand ribcage (increases volume) - extra-embryonic membranes - more efficient systems - better bones and muscles - better teeth and jaws in kinetic skull - tough, dry, scaly - ectothermic - regulate temperature behaviorally - kidneys excrete uric acid (water conserving) - most live in subtropics - Testudines = turtles turtles: - shell fused to ribs and vertebrae - Squamata = liards and snakes snakes: - limbless - tongue collects airborne chemicals - fangs - toxins lizards, crocodiles, alligators: - 4 chambered heart - secondary palate - ectothermic

Mammalia

- evolved from reptiles - diphyodont condition TEETH - Primary (baby) - Deciduous (permanent) - Diphyodont - 2 sets of teeth - heterodont teeth: vary in form and function - incisors: simple crowns, sharp edges, snipping and biting - canines: long, conical crowns, piercing, tearing - premolars: compressed crowns, 1 or 2 cusps, shearing and slicing - molars: large surface area, crushing and grinding HAIR - Body covered with hair (reduced in some) - 2 types of hair, grows in cycles from follicle, shed and replaced (2x/yr) - Hair on surface = dead - Individual hairs made up of 3 layers of keratin - fur coat: - under hair: dense, soft, insulation - so dense it doesn't get wet - guard hair: coarse, longer, protection, coloration - bristles: spines, vibrissae, spiny armor - used to sense, predators, mates, chemicals in environment GLANDS - Sweat glands: tubular, coiled glands for temperature regulation, located in dermis, beneath epidermis - Eccrine sweat glands - watery, hairless body areas - regulate body temp Apocrine - milky fluid, hair follicle - reproduction - Scent glands - vary in location and function, mark territory, defense, warning, reproduction - Sebaceous glands - with hair follicles - produce fatty sebum that protects hair and skin - found over entire body and associated with all hair follicles - Mammary glands - found in females - produce milk = rich in fat, sugar, protein, minerals (calcium) - promotes rapid growth LUNGS + CIRCULATION - highly efficient - well-developed nervous system - adaptable - learn from birth - classified according to reproduction HORNS: 1. TRUE horns: hollow sheaths of keratinized epidermis around a core of bone from the skull; not shed or branched; grow continuously - Get bigger, more curved, heavier over time - Advertise sexual status - their age, fertility, etc. I.e. Bovidae - sheep and cattle 2. ANTLERS: branched and composed of solid bone, covered by velvet (highly vascularized), shed after breeding, next pair larger; only males (except caribou) - For most populations, only males have antlers - For caribou both sexes have antlers - only females keep their antlers year round - males shed theirs in winter and grow new ones next season I.e. Cervidae - deer, caribou 3. RHINOCEROUS horn: hair-like keratinized filaments from dermis matted together, cemented not attached to the skull (does not grow from skull) - makes it possible for poachers to pull off the horn - Medicinal agent (china), aphrodisiac (india), dagger handle (middle east) - none of this is scientifically proven - has driven them to the point of extinction

Tetrapods - Amphibia

- frogs, toads, salamanders, newts - moist, thin, porous, non scaly skin (ectothermic) - jelly-like transparent eggs - laid in water -tied to water by mode of reproduction: animals on land rely on internal fertilization because eggs and sperm dry out very quickly - different means of protecting eggs and sperm on land - Quasiterrestrial = basically aquatic salamanders and newts: - long body, tail, 2 pairs of legs, temperate forests - Side-to-side swaying - Colorful skin patterns - Live in damp areas - under logs, leaves frogs and toads: - tailless as adults - hindlimbs for jumping - tadpole - metamorphosis - goes from aquatic to terrestrial/semi-terrestrial environment - eyes and ears - lungs closed: gills/lungs - positive pressure (they swallow air and force it down into lungs through "buccal pumping") - double-loop circulatory system: Pulmonary and systemic circuits - 3-chambered heart - ectothermic - Aposematic coloration - function of frogs and some salamanders - toxins in skin provide important defense - some have enough toxin to kill 10-20 adults - toxins fall into alkaloid category - Bartesian mimicry - some frogs simply mimic the color of toxic frogs to protect themselves from predators - Amphibian Apocalypse - amphibian fungal panzootic causes catastrophic and ongoing loss of biodiversity

Mollusca - Lophotrochozoan, Eucoelomate, protostome, trochophore larva, head-foot, visceral mass, mantle, mantle cavity, shell (3 layers), radula, gills, lung, open circulatory system (except Cephalopods), countercurrent exchange, H.A.M.

- includes gastropods, bivalves, cephalopods - 110,000 living; 35,000 fossil; tremendous diversity - Have a 3-part body plan: 1. VISCERAL MASS 2. MANTLE 3. HEAD-FOOT - H.A.M. = hypothetical ancestral mollusc (don't believe it ever actually existed, but something similar - we use it to look at mollusc body parts) - Nervous system consists of several ventral ganglia connected by nerve cords - Coelom is reduced and largely limited to the region around the heart - Heart pumps hemolymph through vessels into hemocoel (OPEN CIRCULATION) - Have arteries and veins but no capillaries - RADULA = structure in mouth with teeth - GILLS capture tiny food particles in water

Vertebrates with Jaws = Gnathostomes, jaw evolved from gill slits, Placoderms are early jawed, armored fishes with paired fins

- jaws allowed more efficient prey capture - accompanied by development of 2 airs of appendages - hinged jaws developed from gill arches/slits - Placoderms are early jawed fish (armored, paired fins)

Cnidaria phylum has 4 classes: hydrozoa, scyphozoa, Anthozoa, cubozoa. Hydrozoan life cycle (Obelia) - gastrozooid, gonozooid

- marine and freshwater - OBELIA: genus of hydrozoans - class of mainly marine and some freshwater animal species that have both polyp and medusa stages in their life cycle. - a colony of polyps enclosed by a hard, chitinous covering - feed polyps (GASTROZOOID) - extend beyond covering - have nematocyst-bearing tentacles - reproductive polyps (GONOZOOID) - budding of polyps - Also has sexual reproduction (medusae) stage - Physalia - Portuguese Man of War - polyp colony - Above water sac moves colony around with wind - Warm water species capable of feeding on fish - they get caught in sac

Kingdom Animalia: general characteristics

- multicellularity (dramatic transition 800 mill years ago molecule - Gkpid has played an important role in keeping cells dividing correctly and giving rise to cells that have collected into tissues/multicellular organisms) - heterotrophs - diverse modes (carnivores, herbivores, omnivores, parasites) (breakdown of larger nutrients into smaller pieces to utilize) - no cell walls: flexibility - nervous tissue: rapid response - muscle tissue: movement - sexual reproduction: small, mobile sperm; larger egg; diploid from a blastula; metamorphosis - extracellular matrix (ECM) of collagen *every animal has collagen in body* - special clusters of Hox genes: patterns body axis - similar rRNA - characteristic cell junctions: anchoring, tight, gap

Chondrichthyes - Cartilagenous Fishes = sharks, skates, rays

- skeleton of cartilage - 5 -7 gill slits on each side of head - lack operculum - body covered by placoid (toothlike) scales - teeth are derivatives of placoid scale (dentin, enamel) - Placoid scales - all point in backwards direction - sand papery feel - chemically - lateral line system - can detect bioelectric fields and good sense of smell - liver with squalene - blood is iso-osmotic - with urea and trimethylamine oxide - Heterocercal tail (caudal fin) - one lobe is much smaller than the other - Teeth with dentin and enamel; replaceable - dermal origin 1st two rows (outermost) are active - open-sea predators, rays and skates live on ocean floor - shark-fin soup: served since the Ming dynasty Asian delicacy (primarily China - 95% China has banned it from state functions

Porifera: sponges; cellular level of organization, ostia, oscula, spicules, spongin, choanocytes, pinacocytes, archaeocytes, mesohyl

- sponges are the only animal to have cellular organization (Parazoa) (al other animals are eumetazoa characterized by specialized tissues) Ostia: Saclike bodies perforated by many pores Choanocytes and Oscula: beating of flagella (choanocytes) produces water currents that flow through pores into central cavity and out the (osculum) Archaeocytes Spicules: digest/transport nutrients; made of Spongin, Silicon, CaCO3 Mesohyl: nonliving matrix formed by the spicules - connective tissue of sponge - cells wander through it - support system between outer layer and choanocytes in the body of the sponge Gemmule: a tough-coated dormant cluster of embryonic cells produced by a freshwater sponge for development in more favorable conditions. Pinacocytes: part of the epithelium in sponges. They play a role in movement (contracting and stretching), cell adhesion, signaling, phagocytosis, and polarity. Pinacocytes are filled with mesohyl which is a gel like substance that helps maintain the shape and structure of the sponge.

Platyhelminthes - flatworms, flukes, tapeworms, bilateral symmetry, triploblastic, mesoderm = parenchyma, cephalization, ladder-type nervous system, excretory system (flame cell/protonephridia, tubules), ocelli, pharynx (incomplete gut)

- subphylum of lophotrochozoa (have trochophore-like larvae and are protostomes) FLATWORMS - majority are parasitic (80%) - Organ-level organization: - No specialized circulatory or respiratory structures - CEPHALIZATION - the creation of a distinct head - BILATERAL SYMMETRY - advancement over radial symmetry - LADDER-TYPE nervous system - TRIPLOBLASTIC, but no body cavity yet (acoelomates)

Phylum Tardigrada - tardigrades:

- water bears - 1,000 species - Very small; 0.3-0.5mm - Found in mosses, surface films, aquatic algae, barnacles - Body is short, plump, cylindrical body - Body sits on 4 pairs stubby legs with claws (lobopods) - lumber along like a bear - Piercing stylet apparatus because they eat plant cells - Dorsal brain, ganglionated nerve cord - Malpighian tubules - Dioecious, singular gonad - Mating/egg laying during molting - Direct development - Almost indestructible - can resist to their body losing high amounts of water - can live in ethanol - can be frozen for 30 years and still come back - Cryptobiosis - tun - They go into ball like structure called a tun

Process of Evolution

-Evolution: Heritable change in one or more characteristics of a population or species from one generation to the next -Microevolution: Changes in a single gene in a population over time -Macroevolution: The formation of new species or groups of species PROCESS 1 - Variations are produced by chance mutations and sexual reproduction 2 - Natural selection selects the "fittest" organism 3 - Natural selection leads to adaptation to a particular environment 4 - Process occurs constantly in all species of life on earth -Natural selection acts on individuals in a species -Evolution is a property of populations -Occurs generation to generation -Descendants are different from ancestors -Change in allele (gene) frequencies; change in genetic make-up of population over time (generations)

Evolution in a Genetic Context - Microevolution Hardy-Weinberg Principle

-Microevolution: Accumulations of small changes in the gene pool of a population over a relatively short period of time HARDY-WEINBERG PRINCIPLE -Genes remain in equilibrium (constant frequency) over time (in each succeeding generation of a sexually reproducing population) as long as 5 conditions are met -Relates allele and genotype frequencies in a population -5 CONDITIONS 1. No Mutations → Allelic changes do not occur, or changes in one direction are balanced by changes in the opposite direction (also no gene duplication, exon shuffling, or horizontal gene transfer 2. No Gene Flow → Migration of alleles into or out of the population doesn't occur 3. Random Mating → Individuals pair by chance and not according to their genotypes 4. No Genetic Drift → The population is very large, and changes in allele frequencies due to chance alone are insignificant 5. No Selection → No selective agent favors one genotype over another; all genotypes are equally adapted -EQUATION p + q = 1 p^2 + 2pq + q^2 = 1 p = dominant allele frequency q = recessive allele frequency p^2 = frequency of homozygous dominant genotype q^2 = frequency of homozygous recessive genotype 2pq = frequency of heterozygous genotype -EQUILIBRIUM -If p or q is changed in the next generation, evolution has occurred -Hardy-Weinburg identifies factors that cause evolution -Evolution is detected by noting any deviation from a Hardy-Weinburg equilibrium of allele frequencies in the gene pool of a population -Equilibrium population = hypothetical population in which evolution does not occur -Conditions for Hardy-Weinburg are rarely met -Hardy-Weinburg population provides starting point for studying mechanisms of evolution

11 Body Systems: (of organ-system level animals - lophotrochozoa, gnathifera, ecdysozoa, chordates, etc)

1. INTEGUMENTARY (protection, respiration, nutrient uptake, coloration, temp. regulation) 2. MUSCULAR (movement) 3. SKELETAL (support, leverage, storage) 4. NERVOUS reception of info, analysis, response coordination) 5. ENDOCRINE (regulation of growth, metabolism and sexual development) 6. CIRCULATORY (delivery of O2, nutrients, hormones; removal of CO2, ammonia and wastes) 7. LYMPHATIC (transport, protection, fat absorption) 8. RESPIRATORY (gas exchange) 9. DIGESTIVE (collection of food, breakdown and absorption of nutrients, egestion of wastes) 10. URINARY (water balance, nitrogenous waste elimination) 11. REPRODUCTIVE (procreation)

Allopatric speciation; Adaptive Radiation

ALLOPATRIC SPECIATION -Two geographically isolated populations of one species become different species over time due to interruption of gene flow -Can be due to differing selection pressures in different environments -Example: Kaibab Squirrels -Kaibab squirrel became geographically isolated from the common ancestor with its closest relative, the Abert squirrel, in the North Rim of the Grand Canyon about 10,000 years ago when the Colorado River cut open the Grand Canyon. Since then, several distinguishing features, such as the black belly and forelimbs have gradually evolved. ADAPTIVE RADIATION -When members of a species invade several new geographically separate environments (niches) -The populations adapt to the different environments -Many new species evolve from the single ancestral species -This is an example of allopatric speciation SYMPATRIC SPECIATION -One population develops into two or more reproductively isolated groups -No prior geographic isolation (no physical barriers to interbreeding) -Autoploidy: 2n plant → 2n gametes (+n) = triploid (sterile, seedless) -Alloploidy: Tetraploid hybridization in plants -Results in self-fertile species -Reproductively isolated from either parental species

Subphylum Chelicerates (of arthropoda) - chelicerae, pedipalps, walking legs, horseshoe crabs, carapace, telson, book gills, blood, hemocyanin, Arachnids - spiders, scorpions, ticks, mites, book lungs, poison glands, fangs, silk glands, web, black widow, brown recluse,

Arthropods - Chelicerates: - Siders, scorpions, ticks, mites, horseshoe crabs, sea spiders (74,000; largely terrestrial) - All appendages attached to cephalothorax; none on head (no antennae) - First pair (CHELICERAE) are feeding organs (FANGS) - Second pair (PEDIPALPS) function in feeding or sensory - Horseshoe crabs have BLOOD that clot in the presence of bacteria, because they live in environment full of bacteria so they need to be able to block it off immediately if it gets into their system - LAL = limulus amoebocyte lysate = aqueous extract of blood cells (amoebocytes) from the Atlantic horseshoe crab - BROWN RECLUSE produces a hemolytic toxin - breaks down capillaries and leads to bleeding - BLACK WIDOW = neurotoxic - BOOK LUNGS are within small openings in the abdomen of the arachnid. (plates for respiration) - TELSON = last segment on abdomen - CARAPACE = dorsal section of exoskeleton - HEMOCYANIN = copper-containing respiratory pigments - turn blue on oxygenation - BOOK GILLS = respiratory system

cephalization: incomplete vs. complete digestive system

Cephalization: the formation of a distinct head head - bilaterally symmetrical animals encounter their environment head first - head often contains the sensory organs (anterior end first) Planes: - Frontal plane - dorsal/ventral - Sagittal plane - right/left - Transverse - anterior/posterior - incomplete digestive system: consists of a digestive cavity with one opening. The single opening serves as both mouth and anus. - complete digestive system: consists of a digestive tract with two openings. One opening is the mouth.

Chordata - deuterostomes - 5 chordate characteristics notochord, dorsal hollow nerve cord, pharyngeal pouches (gill slits), postanal tail, also: muscles, ventral heart, endoskeleton, segmentation

CHORDATE CHARACTERISTICS: 1. notochord - provides support and axis for muscle attachment 2. nerve cord - hollow tube - becomes enlarged to form brain 3. pharyngeal pouches (gill slits) - filter-feeding device 4. tail - post-anal - added behind digestive trace for propulsion 5. endostyle - secrete iodinated hormones - lack backbone - muscles work against notochord to move animal - heart located on ventral side of body unlike other animals

Phylum Cnidaria - radial symmetry, diploblastic, tissue level of organization, polymorphism (dimorphism), polyp, medusa, gastrovascular cavity, tentacles, mouth, cnidocytes with nematocysts, nerve net, planula larva, mesoglea, epidermis, gastrodermis

Cnidaria: - tubular animals that most often reside in shallow marine waters - tissue level of organization - DIPLOBLASTIC - RADIAL symmetry - 1 hox gene - POLYMORPHISM: the occurrence of structurally and functionally more than two different types of individuals within the same organism. in cnidarians the POLYP and MEDUSA body forms. - specialized stinging cells (CNIDOCYTES) (fluid-filled capsule - cnidae - with nematocyst) - NEMATOCYST = coiled up fiber - quickly release thread that *fastest occurring biological process known in nature* enough force to break shell of a crustacean - can inject toxins - allow cnidarians to go about feeding and also protect them - only group of organisms that produce nematocysts - 2-layered body sac (outer-layer = protective EPIDERMIS, inner-layer = GASTROVASCULAR cavity with MESOGLEA in between) - NERVE NET found throughout body - PLANULA LARVA: free-swimming or crawling larval type common in many species of the phylum Cnidaria - body is more or less cylindrical or egg-shaped and bears numerous cilia (tiny hairlike projections), which are used for locomotion. - sac body plan (cannot eat continuously)

Evidence for Evolution - Fossil record, Biogeographical evidence, comparative anatomy, embryology; Homologous vs. analogous structures, vestigial structures, comparative biochemistry

FOSSIL RECORD (PALEONTOLOGY) -More than 10,000 yrs old -Records the history of life from the past -Document a succession of life forms from the simple to more complex -Sometimes the fossil record is complete enough to show descent from an ancestor -Transitional Organisms: Specimens found in the fossil record that are common ancestors for two different forms of organisms (reptiles/birds) -Whales → fossil record spans over 50 million years; terrestrial tetrapod to aquatic animals lacking hind limbs BIOGEOGRAPHY -Alfred Russel Wallace - Father of Biogeography -Study of geographical distributions of plants and animals across earth -Different mixes of plants and animals in areas separated by water, continents, islands -Consistent with origin in one locale and then spread to accessible regions -Plate tectonics COMPARATIVE ANATOMY (MORPHOLOGY) -Science of anatomical shape and design -Homologous Structures → Anatomically similar because they are inherited from a common ancestor → May be functionally similar or not -Ex: Vertebrate forelimb -Analogous Structures → Serve the same function but not constructed similarly; do NOT share a common ancestor → Convergent Evolution: Reach same endpoint from different starting point -Analogy: Similarity due to convergence -Ex: Jumping (kangaroo → grasshopper → bullfrog) -Vestigial Structures → Fully-developed anatomical structures; reduced or obsolete function in descendent groups -Ex: Human appendix, wisdom teeth, wings on flightless birds COMPARATIVE DEVELOPMENT (EMBRYOLOGY) -All vertebrate embryos have: -A postanal tail -Paired pharyngeal (gill) pouches -Dorsal, hollow nerve cord -Notochord -"Ontogeny recapitulates Phylogeny" - Ernst Haeckel COMPARATIVE BIOCHEMISTRY -Evidence of Evolution (Modern) -Molecular Homologies → -Almost all living organisms: -Use the same basic biochemical molecules -Utilize same DNA triplet code -Utilize same 20 amino acids in their proteins -Utilize ATP as energy source -Genetic Homologies → -Human and chimpanzee identical -Chicken and turkey identical, duck differ by 1 AA -Human and chicken differ by 13 AAs -Short amino acid sequence in p53 protein (tumor suppressor protein)

Causes of Microevolution - Genetic mutations, gene flow, nonrandom mating (assortative mating and sexual selection, genetic drift, bottleneck effect, founder effect

GENETIC MUTATIONS -The raw material for evolutionary change (source of genetic variability) -Source of new alleles; new combinations of alleles (source on which other evolutionary forces can act) -Not goal-directed; not a result of environmental necessity -Random events - depending on environmental conditions (good, bad, neutral) -Other forces act to either maintain the variation or remove it from the population GENE FLOW -Movement of alleles between populations when -Gametes or seeds (in plants) are carried into another population -Breeding individuals migrate into or out of population -Continual gene flow reduces genetic divergence between populations and typically increases genetic diversity within the population -Populations of relatively sedentary organisms are more isolated from one another than populations of very mobile organisms (subspecies) NONRANDOM MATING -When individuals do not choose mates randomly -Assortative Mating: Individuals select mates with their phenotype and reject opposites (increases # of homozygotes) -Disassortative Mating: Dissimilar phenotypes mate preferentially (increase # of heterozygotes) -Inbreeding: Mating of 2 genetically related individuals; choose a mate with same genetic lineage GENETIC DRIFT -Changes allelic frequency due to random chance -Can cause the gene pools of two isolated populations to become dissimilar -Some alleles are lost (0%) and others become fixed (100%) -Likely to occur: -After a bottleneck -With severe inbreeding -When founders start a new population -A random event prevents a majority of individuals from entering the next generation -Next generation composed of alleles that just happened to make it -Stronger effect in small populations BOTTLENECK EFFECT -Extreme example of genetic drift that happens when the size of a population is severely reduced -African Cheetah -Lost nearly all genetic variability (monomorphic for almost all genes) -Prolonged inbreeding following a bottleneck (10,000 - 12,000 yrs ago) -Very low sperm count, motility, and deformed flagella -Northern Elephant Seals -Low genetic variability -Human inflicted (hunted down to 20 individuals in 1980s) FOUNDER EFFECT -When a new population is started from just a few individuals -The alleles carried by population founders are dictated by chance -Formerly rare alleles will wither occur at a higher frequency in the new population or be absent in the new population -Ellis-van Creveld syndrome (Amish population)

Geological (Biological) Time Scale - Factors influencing patterns Mass Extinctions - importance of them; 1-5+6th

GEOLOGIC TIME SCALE -Life changing over time is a result of -Genetic Changes -Environmental changes -Patterns correlated with -Climate/temp (not uniform across biosphere, changes at different rates) -Atmosphere -Land Masses (Continental drift 1-10 cm/yr) -Floods/glaciation (movement of ice over land) -Volcanic eruptions -Meteorite impacts MASS EXTINCTIONS -Mass Extinction = Big events going on over a relatively short time leading to demise of many forms of life (focus on marine life because there was not always life on land) 1. Ordovician-silurian Extinction (85% marine spp); abrupt climate change (large glaciers) 2. Devonian Extinction (83% marine spp) 3. Permian-triassic Extinction (95% marine spp, LARGEST known due to severe climate change) --> 290-248 mya 4. Triassic-jurassic Extinction (80% marine spp) 5. Cretaceous-tertiary (KT) Extinction (76% marine spp) --> 65 mya; killed dinosauars; meteorite + volcanism 6. (Holocene, Anthropocene Extinction)-Humans acting as global superpredators (current)

invertebrates vs. vertebrates

INVERTEBRATES: lack a backbone - constitute majority (~99%) of animals - >35phyla - no single positive characteristic in common - heterogeneous assemblage of group - sponges, jellyfish, crustaceans, insects, clam, snails, sea stars *FIRST animals were invertebrates* VERTEBRATES: have a backbone - ~1% of animals - 1 phylum (Chordata) - fish, frogs, birds, reptiles, mammals, humans - fishes were the first vertebrates (plants colonized land around same time - provided food for land animals) - life on land - animals developed lungs, internal fertilization, amniotic egg - reptiles dominant for long time before Cambrian explosion A sudden (?) increase in animal diversity occurred during the Cambrian explosion (533 - 525 mya) 3 possible explanations: 1. Favorable environment - warm temperatures, increases in atmospheric and aquatic development of ozone layer 2. Evolution of the Hox gene complex (hox genes regulate which body parts go where) 3. An evolutionary "arms race" - one group develops a protective strategy, their predators come up with strategy to overcome it - both organisms are reshaped

Cephalochordates = lancelets, 4 chordate characteristics as adults

Lancelets; 5-7 cm - Marine, sandy coastal waters - Elongate, fish-like chordates - Notochord and nerve cord run length of body - As adults have all 5 chordate characteristics - Closest vertebrate ancestor (?)

lophotrochozoa, ecdysozoa, phylogenetic tree of animals

Lophotrochozoa & Ecdysozoa: - 2 groups originating from Protostomia (protostomes) - Lophotrochozoa: - include platyhelminthes, rotifera, annelida, and molllusca - Ecdysozoa: - include arthropoda and nematoda - characteristic = molting Phylogenetic Tree of Animals: Clades: - Parazoa (Porifera) - no Hox genes - no specialized tissues from germ layers - closest relative = Placozoa - Placozoa (lost Hox) - multicellular amoebas - Cnidaria (Hox) - 1 hox gene, radial symmetrical diploblastic animals - Ctenophora - may be the group that is most closely related to the origins of the animal kingdom - don't have Hox genes - Basal - Bilateria (Hox) - acoelomates, eucoelomates, pseudocoelomates - bilateral symmetry, triploblastic # of Hox genes increased with complexity of animal - Echinoderms (invertebrates) are most closely related to us (vertebrates) than any other invertebrate because they are deuterostomes - Lophophore = ciliated section used for catching food - Trochophore = ciliated portion that spins and has a gut - gives rise to flatworms - exists in animals and molluscs - Arthropods and nematodes related because they molt their exoskeletons

symmetry: radial, bilateral, sac body plan, tube within a tube body plan

Radiata: 2 identical halves - if you pass any plane through the animals longitudinal axis of oral and aboral, divides the animal into identical halves: (mirror images) - sac body plan - one opening in the gut, can't eat continuously Bilateria - definite right and left halves - only a single plane through longitudinal axis divides the body into left and right mirror images: - tube within a tube body plan - 2 opening in the gut - can eat continuously sac - can't eat continuously tube - can eat continuously

Natural Selection - directional selection, stabilizing selection, disruptive selection, balancing selection

NATURAL SELECTION -Natural Selection: Adaptation of a population to the biotic and abiotic environment -Abiotic = climate, water availability, minerals -Biotic = competetition, predation, sexual selection -Requires: -Variation → The members of a population differ from one another -Inheritance → Many differences are heritable genetic differences -Differential Adaptiveness → Some differences affect survivability -Differential Reproduction → Some differences affect likelihood of successful reproduction -Results In: -A change in allele frequencies in the gene pool -Improved fitness in population -Major cause of microevolution DIRECTIONAL SELECTION -Individuals at one extreme of a phenotypic range have greater reproductive success in a particular environment -Curve shifts in that direction -Examples → Size of modern horse, Industrial/adaptive melanin, DDT-resistant mosquitoes, Antibiotic-resistant bacteria STABILIZING SELECTION -Intermediate phenotype is favored -Peak of curve increases and tails decrease -Examples → human babies with low or high birth weight are less likely to survive, Size of bird clutch greater or less than 4-5 eggs less likely DISRUPTIVE (DIVERSIFYING) SELECTION -Two or more extreme phenotypes are favored over intermediates; bimodal disruption -Can lead to speciation, middle of curve decreases and ends rise BALANCING SELECTION -Maintains genetic diversity -Balanced polymorphism: Two or more alleles are kept in balance and maintained in a population over the course of many generations -Two common ways: -For a single gene, heterozygote favored (heterozygote advantage) -Example: Hbs allele HbA HbA - Malaria: Die HbA Hbs - Sickle Cell Trait Hbs Hbs - Sickle Cell Anemia: Die -Negative frequency-dependent selection (rare individuals have a higher fitness; predator/prey) SEXUAL SELECTION -Directed at certain traits of sexually reproducing species that make it more likely for individuals to find or choose a mate and/or engage in successful mating -In many species, male characteristics are affected more intensely than femlae (sexual dimorphism) -Intrasexual → Same Sex -Males directly compete for mating opportunities or territories -Intersexual → Opposite Sex -Females choose males possessing a particular phenotype

Phylogeny - Phylogenetic tree, Homology, analogy, comparative anatomy, ontogeny, molecular data,

PHYLOGENETIC TREES -Goals of Systematics: Discover all species Reconstruct phylogeny (evolutionary history) Classify accordingly -Phylogeny often represented as a phylogenetic tree -A diagram indicating lines of descent -Each branching point is a divergence from a common ancestor; represents an organism that gives rise to two new groups -Classification lists the unique characters of each taxon and is intended to reflect phylogeny -Primitive Characters → Present in all members of a group and present in the common ancestor -Derived Characters → Present in some members of a group, but absent in the common ancestor HOMOLOGY -Refers to features that stem from a common ancestor -Homologous structures are related to each other through common descent ANALOGY -Convergent Evolution X! -The acquisition of a feature in distantly related lines of descent -Feature is not present in a common ancestor COMPARATIVE ANATOMY = MORPHOLOGY ONTOGENY = EMBRYOLOGY MOLECULAR DATA -Protein comparisons -Immunological techniques: Degree of cross reaction used to judge relationship -Amino Acid sequencing: Similar sequence in same protein indicates close relationship -RNA and DNA comparisons -Two species with similar base-pair sequences are assumed to be closely related -Two species with differing base-pair sequences are assumed to be only distantly related -Molecular Clocks -Use non adaptive nucleotide sequences -Assumed constant rate of (neutral mutations over time) -Favorable mutations are rare -Detrimental mutations are quickly eliminated

Polychaetes, Pogonophorans, Oligochaetes - Earthworms (clitellum, cocoon, dorsal blood vessel), Leeches, suckers, triiradiate (3-part) jaws, hirudin

POLYCHAETES: - 8,000 species - Tremendous diversity - Prostomium - first body segment of worm - hairs, jaws, eyes for seeing - specialized for sensory information and feeding - Peristomeum - area around the worm's mouth - Deposit fecal deposits on the surface of the water column - Parapodia - paired, unjointed lateral outgrowths that bear the chaetae - Some polychaetes protect the major body parts and release the reproductive parts (eggs and sperm) in the epitoky, which breaks off - simultaneous release puts all the egg and sperm of the species in the water column at the same time to ensure successful reproduction - POGONOPHORA: - Specialized group of polychaetes that live in hydrothermal vents deep in the ocean (very active areas of ocean crust) - Anterior cephalic lobe, bearing a beard of 1-1000's ciliated tentacles - Trunk with pair of coelomic cavities - Gut tissue forms an organ (trophosome) that becomes filled with chemosynthetic bacteria - mobilize chemicals around hydrothermal vents in order to produce nutrients that then feed the worms - Segmentation confined to small rear portion (opisthosoma) - - Habitat - near hydrothermal vents EARTH WORM: - The dorsal blood vessels are responsible for carrying blood to the front of the earthworm's body - The clitellum is a swelling of the skin and can only be seen in earthworms that are ready to reproduce - eggs are encased in a cocoon -OLIGOCHAETES: - Do not have well-developed head or parapodia - Chaetae protrude in pairs directly from surface of body - Food drawn into mouth by action of muscular pharynx - Digestion and absorption occur in long internal intestine (Typhlosole for absorption) - Closed circulation - Reproduction - hermaphroditic - Clitellum - secretes mucus to protect: the sperm from desiccation and the cocoon and the albumin - Direct development Hirudinea - LEECHES: - Usually found in freshwater - Same body plan as other annelids (dorsally flattened) - No chaetae; no head - Muscular body wall - No peristalsis - Two additional SUCKERS - Some temporarily parasitic - Keep blood flowing and prevent clotting by means of HIRUDIN, a powerful anticoagulant - TRIIRADIATE (3 part) jaws - pharynx - shape of a peace sign - you don't feel their bite because of their aesthetic quality - They find you by cuing in on your body temperature

protostome, deuterostome, segmentation (metamerism)

Protostome: 1st embryonic opening becomes the mouth (most of Bilateria: Annelids, Arthropods, Molluscs) - Determinate cleavage (spiral cleavage) - Mosaic embryo: each part of cell becomes part of the animals body - Schizocoely - Blastopore becomes mouth - Coelom comes about as a slitting between the mesodermal bands Deuterostome: 2nd embryonic opening becomes the mouth (Echinoderms, Chordates) - Indeterminate cleavage (radial cleavage) (cells divide at 90 degree angles - top/sides) - regulative embryo - stem cells: pluripotent: when cells split, each one still has potential to give rise to all the structures in the animal's body - you get identicals = regulative embryo - Enterocoely - Blastopore becomes anus - Coelom forms from outpocketing of the Archenteron - called enterocoely - End result of schizocoely and enterocoely is the same Segmentation: - Body may be divided into regions called segments - Occurs in annelid worms, arthropods, and chordates - Allows specialization of body regions

Symbiosis, Aposmatism, Leucism

SYMBIOSIS -Mutualism = Everybody happy -Commensalism = Happy host, neutral simbiont -Parasitism = Harmed host, happy parasite APOSMATISM -Warning Coloration -Red, yellow, black, white -Brilliant patterns/colors associated with toxic or distasteful substances -Sponges, sea slugs, soft corals, tunicates, polyclad flatworms, insects, amphibians -Antipredator strategy: Beneficial for both predator and prey -Mimicry → organisms that mimic can obtain the same benefits -Batesian Mimicry: Non toxic species resembling toxic species LEUCISM -Leucism is an autosomal recessive condition that results in a perfectly white animal (a white morph) due to a defect in the skin, not in the pigment cells. -It is a naturally occurring rare trait seen in birds, mammals, reptiles, amphibians, and even fish. -White tigers in captivity have been inbred to produce this trait for commercial value. -In contrast to albinism, a condition caused by a different mutation, leucistic animals typically have normally colored eyes. -There are several populations of eastern gray squirrels (Sciurus carolinensis) across the United States where this trait is notable including Missouri, Illinois, Florida, North Carolina, and Tennessee. -These squirrels differ only in color from their gray counterparts. In Massachusetts, residents of the Ballardvale section of Andover began observing white squirrels in the local population in 2009-2010. The population continued to grow and spread such that the local newspapers reported on the phenomenon in 2016. More recently, the squirrels have been a featured subject on the WCVB show "Chronicle." Watch

Subphylum Crustaceans (of arthropoda) - antennae, mandibles, maxillae, biramous appendages, swimmerets, uropods, molting, barnacles, water fleas, copepods, lobster, crab, crayfish

Shrimp, lobsters, crayfish, crabs, barnacles - 45,000 species - Thorax bears 5 pairs of walking legs (BIRAMOUS - upper part exopod - under part endopod): - 1st pair = chelipeds - Head and thorax fused into cephalothorax: - Covered by non segmented carapace - 2 pairs antenna - 1 pair compound eyes - Abdominal segments with SWIMMERETES; tail = UROPODS - Used for locomotion and escape - Respiratory system - gills - feathery appendages that are ventilated Decapod = lobster Krill, water flea *have adaptations that allow them to very successful in terrestrial and aquatic environments*

Asconoid, Syconoid, Leuconoid, spongocoel, sessile filter feeder, sexual and asexual reproduction, gemmules:

Simplest sponges are of the ASCONOID variety: - Small, tube-shaped - Flagellated SPONGOCOEL - Water flows through the osteo, into the spongocoel, and exits the osculum -i.e. bath sponge SYCONOID sponges: - tubular body - flagellated canals - i.e. glass sponge LEUCONOID sponges (vast majority ~96% of sponges) - Most complex - Largest sponges - Large colonial masses - some have spicules of silica, some of calcium carbonate - Many flagellated chambers - Water comes in the ostea, through the incurrent canals, exits out the excurrent canals, and goes to multiple oscula -i.e. barrel sponge - SESSILE (cannot move) FILTER FEEDERS (choanocytes draw nutrients from water in) - sexual and asexual reproduction: - ASEXUAL reproduction by fragmentation or budding - most poriferans that reproduce by SEXUAL means are hermaphroditic and produce eggs and sperm at different times. Sperm are frequently "broadcast" into the water column. GEMMULES - created by freshwater sponges - green balls - bundles of unspecialized cells in a capsule - allow sponges to survive harsh conditions (i.e. freezing weather) and then come back to life when conditions are more favorable Why do we care about flow of water through body of sponge? V = 1/A Velocity of water flow (V) = 1/cross sectional surface area of the flagellated chambers (A) The more cross sectional chambers there are, the greater the surface area, the slower the flow of the water, the longer the sponge can feed, the bigger the sponge gets

Monophyletic groups, Polyphyletic groups, Paraphyletic groups

TRADITIONAL SYSTEMSTICS -Mainly uses anatomical data -Classify organisms using assumed phylogeny with emphasis on phenotype -Stress both common ancestry and degree of structural difference among divergent groups -Construct phylogenetic trees by applying evolutionary principles to categories -Not Strict in making sure all taxa are monophyletic -Monophyly preferred, Paraphyly accepted, Polyphyly never ok MONOPHYLETIC GROUPS -Taxon whose units all evolved from a single parent stock; Most recent common ancestor and all of its descendents PARAPHYLETIC GROUP -Includes common ancestor but not all descendants POLYPHYLETIC GROUP -Members traced to separate ancestors -Does not contain the most recent common ancestor of the group

Tetrapods

Tetrapods = amphibians + amniotes (reptiles, birds, mammals) - 4 limbs - air is less buoyant on land - 20x more O2 - Movement onto land = single most dramatic event in animal evolution: Requires a different circulatory and skeletal system, different brain, hearing apparatus for air, better balance, vision, etc. Stronger respiratory and circulatory systems Better vision, hearing, balance, expanded brain

Choanoflagellates

The choanoflagellates are a group of free-living unicellular and colonial flagellate eukaryotes considered to be the closest living relatives of the animals. Choanoflagellates are among the closest living single-celled relatives of metazoans. This relationship means that choanoflagellates are to metazoans — all animals, from sponges to flatworms to chordates — what chimpanzees are to humans. Metazoan animals are multicellular, mitochondrial eukaryotes. Today Metazoa encompasses all animals with differentiated tissues, including nerves and muscles. They evolved from the protists approximately 700 million years ago.

Flukes - complex life cycle, definitive host, intermediate hosts, miracidium, sporocysts, redia, cercariae, metacercariae, adult, Chlonorchis sinensis, Schistosoma spp.

Trematodes (FLUKES): parasitic flatworms - largest group of flatworms: - Reproductive system well-developed - Usually hermaphroditic - Complex life cycle (*Clonorchis sinensis - Liver fluke*: Humans the DEFINITIVE HOST - harbors sexually mature stage of parasite in which it engages in sexual reproduction - Feed on your liver and inflame bile ducts) - LIFE CYCLE: embryonated eggs passed in human feces - eggs ingested by snail - caercariae encyst in skin or flesh of fresh water fish - metacercariae in fish are injested by human host - excyst in duodenum - adults in biliary duct - INTERMEDIATE host - harbors sexually immature parasite - symptoms = abdominal pain, diarrhea Cestodes (Tapeworms) *SCHISTOMIASIS infects people: - larvae penetrate skin of human (DEFINITIVE host) and mature in the liver - adult worms live and copulate in blood vessels of human gut - eggs migrate into digestive tract and are passed in feces - ciliated larvae (MIRACIDA) hatch in water and enter snail, the INTERMEDIATE host - mother sporocyst in snail encloses many developing daughter sporocysts which enclose larvae (CERICARIAE) - larvae break out of daughter sporocysts, escape snail, and enter water. - symptoms = rash, itchy skin, chills, headache

Vertebrates - Craniates - hagfishes, cylindrical body, no fins, and smooth nonscaly skin, slime

VERTEBRATES: - chordates with a backbone - chordate characteristics + vertebral column + cranium + endoskeleton of cartilage or bone Cyclostomata: hagfish and lamphreys - HAGFISH: - "Slime eels" marine - Lack eyes, jaws, fins, and vertebrae - Cartilaginous skull + notochord - Scavengers - Blind, keen smell and touch - Live in burrows on cold ocean floor - Attach rasping tongue to body of other fishes to feed - Defense: Enormous quantities of SLIME - Extensive flexibility

Insects (Hexapoda - subphylum of Arthropoda) : 3 prs legs, wings, diverse mouthparts, tracheal system, metamorphosis, instar, holometabolous, larva, pupa, hemimetabolous, nymph, ametabolous

_Arthropods - Uniramians (biggest and most diverse group of arthropods) - Hexapoda (insects) and - Myriapoda (millipedes and centipedes) >1 mill species - Appendages attached to the thorax and abdomen only have one branch (uniramious) - 3 pairs legs, 0-2 pairs wings live on land and breathe by TRACHEAE - Chilopoda = centipedes: - Flattened dorsoventrally - Fast carnivores - Poison glands - Diplopods = millipedes - 10,000 species - Rounded body - Slow-moving deposit feeders - Only means of defense is to curl up into a ball Uniramian Diversity: Butterflies, dragonflies, moths, termites, beetles, ants, and more - Largely characterized by ability to fly - Insect metamorphosis: - AMETABULOUS = no METAMORPHOSIS (process of transformation from an immature form to an adult form in two or more distinct stages) - HOLOMETBULOUS (88% of insects) = complete metamorphosis - HEMIMETABULOUS = gradual change throughout development - i.e. molting skin progressively - 4 stages on insect development: NYMPH (egg) -> LARVA -> PUPA -> ADULT

Coelom: importance, acoelomate, pseudocoelomate, eucoelomate

coelom = fluid-filled space around the gut in which organs are suspended benefits: more space, more SA, support (hydrostatic skeleton), increased body size/complexity, allows internal organs to grow freely, serves for gas transport, sperm/egg storage, waste reservoir acoelomate = no body cavity (no coelom) - i.e. flatworms (platyhelminthes) - triploblastic *acoelomates are triploblastic* A pseudocoelomate is an organism with body cavity that is not derived from the mesoderm, as in a true coelom, or body cavity. They have a fluid-filled body cavity separating the gut of the organism from the body wall but it is not lined by mesoderm, unlike true coelomates. - nematodes, rotifers Eucoelomates: (eu=true - "true" coelomates) Body cavity lined on all sides by mesoderm derived tissue

Classifications: diploblastic, triploblastic, endoderm, mesoderm, ectoderm

endoderm, mesoderm, ectoderm = germ layers - groups of cells that behave as a unit during embryonic development - gives rise to tissue/organ system (morphogenesis) diploblastic = 2 germ layers (ectoderm and endoderm with nonliving mesoglea inbetween) i.e. cnidarians triploblastic = 3 germ layers (ectoderm outside, endoderm inside with mesoderm inbetween - mesoderm gives rise to muscles, connective tissues, fat stores, internal organs