Exam4 (Final)

1. At maximum warming conditions, most nests would result in _______. A. All male tuatara offspring B. All female tuatara offspring C. A mix of male and female tuatara offspring D. No offspring

A. All male tuatara offspring

2. Which is not a modification for flight: A. Feathers B. Hollow bones C. Diapsid Skull D. Absence of urinary bladder

A. Feathers

All venomous snakes stem from one snake with fangs at the back of the mouth A. True B. False

A. True

Class Aves - Neognathae

• All the non-Paelognathous birds! • Very diverse...too many groups to list here or cover today.

Other adaptations for flight...

• Reduction in reproductive redundancies • No urinary bladder, uric acid excretion • Highly developed sensory perception

Avian Respiratory System

• Relatively small lungs • Extensive system of air sacs that connect to lungs • Air flows to posterior air sacs, to the lung, to the anterior air sacs, then out • Air only moves in one direction through lungs

The Amniote Egg

• Amnion - suspends embryo in amniotic fluid • Allantois - stores metabolic wastes • Yolk sac - nutrient storage • Chorion - vascularized for gas exchange

Rib Ventilation of Lungs

• Amniotes have more efficient lungs • Movements of muscles attached to ribs causes lungs to expand/contract • Negative pressure breathing • This allows a long neck, because rib ventilation can force air in & out of a long trachea

tetrapod means:

"four feet"

Ballistic Tongue Flipping

(Rana)

4. Paleognathae is the sister taxa to which clade? A. Neognathae B. Tinamous C. Pelycosaurs D. Eutherians

A. Neognathae

2. Why are bats so important to the economy? A. They consume incredible amounts of insects and decrease the need for pesticides B. They are an important tourist attraction C. There is not enough data to know if they are important D. Their feces can be used as fertilizer

A. They consume incredible amounts of insects and decrease the need for pesticides

Relatively speaking, placental mammals tend to have longer gestation periods and shorter lactation periods than marsupials. A. True B. False

A. True

Is this snake A. elapid B. viper

A. elapid

Birds are all of the following EXCEPT A. Diapsids B. Ectotherms C.Archosaurs D.Amniotes E. Vertebrates

B. Ectotherms

4.What is the proximate cause of turtles having a plastron? A. Their bellies get all scratched up without it, so they need it. B. Evolution favored the plastron bones over the typical ventral anatomy. C. Without the evolution of the plastron, turtles would be more endangered and could not make more babies. D. The typical ventral anatomy is more effective than the growth of the bridge bones because these bones don't connect well to the carapace.

B. Evolution favored the plastron bones over the typical ventral anatomy.

True or False: Polyandry is a mating system that involves one male mating with multiple females A. True B. False

B. False

Most snakes are venomous A. True B. False

B. False (Less than 20% of all snakes are venomous except in Australia)

The type of sex determination a clade exhibits is very consistent. A. True B. False

B. False (Sex determination is very evolutionarily labile)

If a species has temperature-dependent sex determination, males have a Y-chromosome: A. True B. False

B. False (there are no sex chromosomes)

3. Piping Plovers that were categorized as disappeared were commonly: A. Male B. Female C. Relatively young D. Of odd coloration

B. Female

2. Studying the Firgatebirds gives humans the chance the better understand? A. How to reduce air drag when flying through thermals in airplanes? B. How to combat fatigue? C. How to catch a Frigatebird in the wild? D. The difference between the Frigatebird and the Sandpiper Shorebirds

B. How to combat fatigue?

The fossil Tiktaalik represents the transition between A. Amphibians & amniotes B. Lobe-finned fishes & tetrapods C.Reptiles & birds D. Jawless fishes & Gnathostomes E. Amphibians & reptiles

B. Lobe-finned fishes & tetrapods

A turtle's ventral shell/plate is called the A. Carapace B. Plastron C.Test D. Cloaca E. Chorion

B. Plastron

1. Which of the following is not a function of amphibian skin? A. Gas exchange B. Reproduction C. Respiration D. Water absorption

B. Reproduction

1. Which is the osteochondrogenic transcription factor that when it is absent, cells can become cartilage or bone and when it is present the bones are committed to osteogenesis? A. Hox6 B. Runx2 C. Sox9 D. G12

B. Runx2

Which reptile group contains the most number of species? A. Turtles B. Squamates C.Crocodilians D. Tuatara

B. Squamates (Lizards and Snakes)

Sex in crocodilians is determined by A. XY chromosomes B. Temperature C. pH D. ZW chromosomes E. Male quality

B. Temperature

3. The clade Eutheria means "true beast". What is the defining characteristic of this clade? A. They can fly B. They have a placenta C. They are solely carnivorous D. They have pouches

B. They have a placenta

Which of the following do not belong to clade Archosauria? A. Crocodilians B. Turtles C.Birds D. Dinosaurs E. Pterosaurs

B. Turtles

Amphibians transmit sound with a: A. Lateral line system B. Typanic membrane and stapes C. Incus and malleus D. saccule and utricle

B. Typanic membrane and stapes

vocalization in Order Anura

Buccal-lung cycling across glottis

Gas exchange in amphibians occurs A.Through the skin B.By gills C.Through lungs D.Through the mouth E.All above

E.All above

How to go from feathered runner to a flier? What use is half a wing???

Wing-assisted incline running (WAIR)

Lungs originally evolved to:

help breath in anoxic water where O2 is depleted

Iguania

iguanas anoles fence lizards horned lizards agamids chameleons

Gas exchange across the skin =

primary means of respiration in many terrestrial salamanders

Simple Tongue Extension

(Ambystoma)

Ballistic Tongue Projection

(Hydromantes)

3. Activity in dogs brain systems devoted to interpreting vocal sounds changes in similar ways to humans depending on the _____. A. tone of the vocalization B. volume of the vocalization C. length of the vocalization

A. tone of the vocalization

Venom evolved multiple times A. True B. False

B. False

Order Crocodilia

Divided into three groups: • Gharials (long, narrow snout) • Alligators & Caimans (broad snout, lower teeth not visible when mouth is closed) • Crocodiles (lower teeth visible when mouth is closed) •Originated 240-250mya •Sister taxa to birds/dinosaurs •At least five crocodilian lineages (the caimans, the American alligator, the Chinese alligator, the crocodiles, and the gharial/false gharial clade) •Survived the K/T extinction 65 mya

Colubridae

Garter snake, boomslang, ring-necked, and about 2000 other species

Elapidae

cobras and mambas; coral snakes; terrestrial kraits; brown snakes, taipans, and death adders; sea kraits; and seasnakes ~325 species

VIT genes

code for an egg yolk protein (delivers essential nutrients to developing birds & reptiles)

Order Testudines

(Turtles) • ~300 species • Tortoise = terrestrial • Earliest known turtle fossil 210 mya • Fossil turtles very similar to modern turtles • Shell made of fused bony plates • Dorsal = carapace • Ventral = plastron • Ribs usually fused to carapace • No teeth, have a sharp beak

Order Gymnophiona

(caecilians) • "Naked snakes" • ~200 living species • Tropical forests • Burrowing • Eyes often vestigial • Internal fertilization

Order Anura

(frogs & toads) • "Without tail" • 21 families, including • Bufonidae • Ranidae • Hylidae

Monotremes

(platypus and echidna) are basal to, and equally distantly related to the marsupials and the eutherians. Split ~200-215 mya** ((Split of marsupials and the eutherians is also really ancient ~175-200mya))

Order Urodela

(salamanders) • "Evident tail" • ~670 living species (salamanders) • Carnivorous • Internal fertilization via spermatophore • Many have direct development • Some are paedomorphic

Temperature-dependent Sex Determination (TSD)

1) Sex not determined at conception 2) Sex determined, irreversibly due to the temperature during a critical period of development 3) We do not know how this works on a molecular level

2. What is the "chytrid" fungus attracted to in amphibian skin? A. Keratin B. Toxins C. Mucus D. Water

A. Keratin

Which group of mammals is oviparous? A. Monotremes B. Marsupials C.Eutherians D. Polytherians

A. Monotremes

Origins of Flight: Two theories

1. Trees Down Theory Birds started as arboreal climbers Learned to glide first, then later to fly 2. Ground Up (Cursorial) Theory Birds started as terrestrial runners

Tetrapod move from water to land:

390-360 mya Devonian Period

2.The ancestors of turtles are closely related to: A. Reptiles B. Crocodiles/ Alligators C. Amphibians D. Their ancestor is an animal thought to be extinct, but showed signs of a underdeveloped carapace.

A or B???????? NO IDEA

3. What characteristic describe the Frigatebird? A. Black feather, long forked tails, and hooked bills B. Long red tail, short beak C. Large wings, blue tail, and strong pectoral muscles D. Small wings, green feathers.

A. Black feather, long forked tails, and hooked bills

Snakes flick their tongues into the air and then back into their mouths in order to A. Collect scent molecules that are sensed by a special organ in the mouth B. Sense very subtle differences in heat that can lead them to prey C. Feel the temperature of the air (so they know if they should bask or seek shade)

A. Collect scent molecules that are sensed by a special organ in the mouth (Jacobson's organ)

Newly hatched birds that are naked and unable to walk are called __________. A. Precocial B. Altricial C.Intermediate D. Lazy

B. Altricial

1. What makes the bat and rat suitable for comparison in a study? A. Both taxonomic orders are evolutionarily ancient B. Both are diverse and include many species with peridomestic habits C. Both species that commonly express torpor D. All of the above

B. Both are diverse and include many species with peridomestic habits

The amphibians that no longer use four limbs are the A. Snakes B. Caecilians C. Salamanders D. Frogs E. Glass lizards

B. Caecilians

Birds are the sister group of which clade? A. Turtles B. Crocodilians C.Snakes D. Tuataras E. Mammals

B. Crocodilians

1. What does Paleognathae mean in ancient Greek? A. "no beak" B. "feather duster" C. "old jaw" D. "reptile jaw"

C. "old jaw"

4. The research had two sets of temperature other than current temp for their predictions, what were they? A. +.1-.8 ℃ B. +2.1- 2.7 ℃ C. +4 ℃ D. Both (a) and (c) are correct D. Both (b) and (c) are correct

C. +4 ℃

4. What is the definition of "zoonotic"? A. It is a disease or virus you obtain from going to the zoo B. The viruses are spread by pollination C. A disease that is transmittable from animals to people D. Viruses or diseases that are spread from animal to animal

C. A disease that is transmittable from animals to people

4. Researching nest abandonment is important because? A. Want to know how many Piping Plovers are dying B. Because abandoned nests have to be removed C. Because Piping Plovers are endangered and researchers need to understand why reproduction rates are decreasing D. Because abandoned nests may be used by other species

C. Because Piping Plovers are endangered and researchers need to understand why reproduction rates are decreasing

3. At which stage of plastron development do the bridge bones start developing off the plastron? A. G15 B. G16 C. G18 D. G21

C. G18

Why are there so few tuataras in the world? A. Their skins are very desirable for shoes & handbags B. They are considered a delicacy in some parts of the world C. Introduced domestic animals have preyed upon them and destroyed their habitats D. They have slow growth rates and low reproductive rates E. More than one of the above are correct

C. Introduced domestic animals have preyed upon them and destroyed their habitats D. They have slow growth rates and low reproductive rates E. More than one of the above are correct

All of the following were challenges of the vertebrate move to land EXCEPT A. Less structural support from air than water B. Bigger temperature fluctuations in air than water C. Lack of oxygen D. Diversity of habitats E. All of the above were challenges

C. Lack of oxygen

1. Which equipment was NOT used on the Frigatebirds to test their sleeping habits? A. EEG B. Accelerometer C. MRI D. GPS data-logger

C. MRI

1. Piping Plovers are found in all of the following EXCEPT: A. Great Plains B. Atlantic coast C. Pacific coast D. Gulf Coast

C. Pacific coast

Mammals are A. Anapsids B. Diapsids C. Synapsids D. Triapsids

C. Synapsids

How do turtles deal with the fact that they can 't expand their chests to breathe (because of their shells)? A. They breathe via the skin, like amphibians B. They have a true diaphragm, just like birds and mammals C. They use abdominal and pectoral muscles like a diaphragm D. Aquatic turtles have gills instead of lungs

C. They use abdominal and pectoral muscles like a diaphragm

2. What is an effect of low genetic diversity in tuataras? A. The tuataras would be the same, nothing will change B. The populations will increase C. Tuataras wouldn't adapt to fast changes in the environment D. The population will continue to evolve

C. Tuataras wouldn't adapt to fast changes in the environment

4. What type of sleep is seen when the Frigatebird is sleeping with one half of its brain awake, while the other half is asleep? A. Bihemispheric sleep B. Completely asleep C. Unihemispheric slow-wave sleep D. Completely awake

C. Unihemispheric slow-wave sleep

The tetrapods include which two major extant groups? A. Dipneusta & Amphibia B. Actinopterygii & Sarcopterygii C.Amphibia & Amniota D. Amniota & Mammalia E. Agnatha & Gnathostomata

C.Amphibia & Amniota

Which type of skull is this? A. Synapsid B. Anapsid C.Diapsid D. Triapsid E. Polyapsid

C.Diapsid

Unique mammalian features include all of the following EXCEPT A. Hair B. Sweat glands C.Homodont teeth D. Lactation

C.Homodont teeth

Which of these animals are NOT part of the Order Squamata? A. Monitors B. Lizards C.Tuataras D. Snakes

C.Tuataras

Viperidae

Copperheads, cottonmouths, rattlesnakes, Fer de lance, Bush master, ~220 species

4. People with psychopathic traits are less likely to catch a yawn from the people around them because they __________. A. lack empathy B. don't make emotional connections with others C. lack a conscience D. A and B E. All of the above

D. A and B

4. What are amphibian's main line of defense against diseases? A. Peptides B. Lysozymes C. Metabolic products from symbiotic bacteria D. All of the above

D. All of the above

Which of the following changes happened during the evolution of mammals from a synapsid ancestor? A. Small bones that were once part of the jaw became part of the inner ear B. Enlarged cranium and redesigned jaws C.Teeth are replaced only once, instead of throughout life D. All of the above

D. All of the above

All of the following are diapsids EXCEPT A. Crocodiles B. Turtles C.Birds D. Mammals E. Snakes

D. Mammals

3. The palate in vertebrates serves what purpose? A. Used to eat dinner off of B. A supportive structure near the tailbone C. Separates the brain from the nasal and oral cavities D. Separates the nasal and oral cavities

D. Separates the nasal and oral cavities

Avian adaptations for flight include all of the following EXCEPT A. Pneumatized bones B. Keeled sternum C.Fused clavicle D. Strong dorsal flight muscles E. Vestigial right oviduct and ovary

D. Strong dorsal flight muscles

3. How does the "chytrid" fungus spread? A. Airborne spores B. Contaminating bodies of water C. Skin to skin contact D. b and c E. None of the above

D. b and c

2. In this study, what was emu oil used to treat? A. Inflammatory Bowel Disease B. Male pattern baldness C. sunburns D. radiation dermatitis

D. radiation dermatitis

3. Which of the following factors contribute to declining tuatara populations? A. Poaching and over harvest B. Rising average temperatures (global warming) C. Longevity seen in tuataras D. Both (a) and (b) are correct E. Both (b) and (c) are correct

E. Both (b) and (c) are correct

2. Dogs are more likely to yawn when exposed to which stimuli: A. Visual-auditory B. Mouth movement C. Audio only D. Conspecific yawning E. Equal response among stimuli

E. Equal response among stimuli

Amniotes are characterized by all of the following EXCEPT A. Four extraembryonic membranes B. Relatively strong jaws C.Rib ventilation of the lungs D. Thicker skin E. Exclusively external fertilization

E. Exclusively external fertilization

1. True/False - The study conducted found a correlation between dogs' yawning and empathy.

False

Insulation

Hair Subcutaneous fat Sweat and sebaceous glands Blood vessels

Origin & Evolution of Mammals

History: • Evolution of mammals from earliest amniote ancestors is well documented • Skull structures, especially teeth, provide abundant evidence of evolutionary descent • Large adaptive radiation occurred in the Cenozoic, when dinosaurs (excluding birds) went extinct (65mya)

Lineage to present-day :

Homo split from other great apes 6 -10mya

Marsupials Convergent Evolution

In Australia, convergent evolution has resulted in a diversity of marsupials that resemble eutherian mammals elsewhere

Kinetic Skull

Lizard

Prototheria: Monotremes

Platypus & 2 echidna species • All three Australia or New Guinea • Probably evolved before other kinds of mammals • **Oviparous** • Eggs have thin, leathery shell • Young hatch in a relatively undeveloped state • Echidnas have abdominal pouch where they hold the eggs & hatched young • Platypuses curl around the eggs to protect them, hatched young stay on motherʼs abdomen. • Young feed on milk • No nipples - milk "sweated" into indentation on motherʼs abdomen

Autotomy

Tail separation

Herpetology

the study of amphibians (including frogs, toads, salamanders, newts, and caecilians) and reptiles (including snakes, lizards, turtles, crocodilians, and the tuataras).

Turtles vs tortoises

turtles: mainly aquatic tortoises: terrestrial

Apes

• "Apes" (gibbons, orangutans, gorillas, chimps) • Humans & extinct humanlike anthropoid species (hominins) • No tail • Start to develop bipedalism • Adaptations for bipedalism in hominins • Bowl-shaped pelvis • Spine curved in an S-shape • Short toes, front facing toes

Order Squamata

• 5810 lizard species, 3370 snake species • Most diverse group of reptiles in body plan • Upper jaw loosely joined to skull • Kinetic skull (cranial kinesis)

Some more mammalian characteristics

• Amniotes, with characteristic fetal membranes • Highly developed brain

Amniotes

• Amniotic egg • Thicker, more waterproof skin • Stronger jaws • High-pressure cardiovascular system • Excretory system that conserves water

Corollaries of Ground Up Hypothesis

• Ancestor of birds was bipedal (i.e., probably a theropod dinosaur) • Feathers preceded the origin of avian flight because a bipedal terrestrial bird ancestor can only take off if it already has proto-wings capable of generating lift • If feathers preceded flight, this must be due to some other advantage of feathers

Amniote Excretory System

• Aquatic organisms - ammonia • Amphibians - ammonia from egg and larvae, urea from adults • Most reptiles & other amniotes - uric acid

Amphibia lifecycle

• Characteristic (ancestral) life history that includes aquatic larvae & terrestrial adults • Mostly oviparous; yolky eggs with jellylike membrane coverings

Eutherians

• Complete embryonic development in uterus • Placenta joins developing young to mother • Relatively long gestation & shorter lactation • Larger animals have longer gestation periods* • 95% of mammals are eutherian • 18 orders - lots of diversity

Feather types

• Contour feathers are vaned feathers that cover & streamline the body • Flight feathers extend beyond the body • Down feathers are soft & have no hooks on the barbules • Filoplume feathers are hairlike - function unclear • Powder-down feathers disintegrate as they grow, releasing powder that aids in waterproofing

What challenges did vertebrates face during their move to land?

• Density of medium reduced (decreased structural support, etc.) • Increased temperature fluctuation

Amphibia are endo or ectothermic?

• Ectothermic

Efficient gas exchange

• Enucleated blood cells—reduced sizeàfiner capillary beds • Lungs with alveoli • Muscular diaphragm—negative pressure respiration • 4-chambered heart—origin independent of archosaurs

Charnov-Bull Hypothesis for why TSD is adaptive

• Environment patchy • Some patches lead to better fitness for developing males • Some patches lead to better fitness for developing females • But the lizard/turtle/croc does not know which patch it will end up in during development. • Thus, best to wait to determine sex after the embryo is in its developmental patch

Early tetrapod transition:

• Eusthenopteron - 385 mya • Pandericthys - 380 mya • Tiktaalik - 375 mya • Acanthostega - 365 mya • Icthyostega - 363 mya

Lizards

• Every continent except Antarctica • Most prey on insects or other small animals • Very few are venomous • Autotomy in some • Squamates, generally, have skull kinesis

How do they know to go?

• External factor: Variation in day length • Internal factors: Energy balance & state of gonads

Australopithecus sp.

• First fossil found was nicknamed "Lucy" • Australopithecus afarensis • Paraphyletic group • Some species walked fully erect & had human-like hands & teeth • Brains smaller (400cc) than modern humans (1400cc) • ~3.7 - 3.0 mya

What about flightless birds?

• Flightlessness has evolved in many groups of birds • Many flightless fossil forms (owls, pigeons, parrots, cranes, ducks, & auks) • Ratites (Paleognathus birds) are all flightless (ostriches, cassowaries, emus, rheas, kiwis) • Penguins (use wings to swim) • Usually occurs on islands with few predators

Characteristics of Tetrapoda

• Four limbs: one bone, two bones, wrist, digits (ancestrally 8 digits in front and 7 behind--Ichthyostega) • Neck—separation of pectoral girdle and skull • Paired internal nares serving in chemoreception, respiration (nostrils connect to mouth) • Hyomandibula (formerly a bone of the jaw joint) functions in hearing

Feathers (cont...)

• Fully grown feathers are dead - like mammalian hair • Birds molt to replace worn out feathers • Usually feathers discarded gradually to avoid bare spots • Flight feathers & tail feathers are lost in pairs to maintain balance • Many waterfowl lose all primary feathers at once and are grounded during the molt

Why migrate?

• Going south for the winter: • Weather is better • More food in the south • Longer daylight hours to search for food • Breeding in the north: • Breeding grounds not as crowded • Abundant food • Longer daylight hours to search for food • Predators not as adapted to eating you if youʼre only around for a few months in the summer (migration disrupts predation)

Main causes in Amphibia declines:

• Habitat alteration/loss • Contaminants (pesticides, herbicides, industrial pollutants, etc.) • Introduced predators (fish, bullfrogs, etc.) • Diseases (fungal & viral) • Climate change

Mammalian Characteristics

• Hair • Characteristic integument (skin) with glands • Mammary glands & milk • Diphyodont teeth (two sets), mostly heterodont (different shape, size)

Complex dentition

• Heterodont • Diphyodont

A few other important bird characteristics...

• Hind limbs adapted for walking, swimming, or perching (variation in foot structure) • Flexor tendons in Passerines • Shelled amniotic eggs • Keratinized bills (beaks) • Most have kinetic skulls • Upper jaw attached loosely = wide gape

Fossil Hominins

• Hominins = apes that are more closely related to us than chimps • Several hominins arose, thrived, and went extinct over the past 4.4 million years • Different hominin species coexisted over the same time periods

Bird Mating Systems (cont...)

• However, many individuals do not do this—why not? • Possible costs of EPCs for males: • Sperm depletion & ejaculate production cost • Increased risk of cuckoldry • Reduction in parental care • Increased likelihood of divorce • Possible costs of EPCs for females: • Male retaliation • Risk of injury • Harassment from extra-pair (or potential extra-pair) males

One example of TSD:

• In turtles, adult females are larger than adult males • Larger females produce more eggs than smaller females • Low incubation temperatures produce smaller hatchlings • High incubation temperatures produce larger hatchlings • Thus, better for females to be produced at higher temperatures so they can get a head start on being larger.

Primate Characteristics

• Increased importance of vision • Decreased importance of olfaction (smaller olfactory bulb related to total brain size) • Grasping hands & feet • Nails instead of claws • Large brain • Front facing eyes • Post-orbital bar

How do they know WHERE to go?

• Landmarks • Position of sun • Position of stars • Earth's magnetic field • Young may have innate knowledge of route, or they may migrate with adults of their species • Many birds return to same breeding site year after year, and same wintering site

Parental Care Example: Alligators

• Lay eggs terrestrially • Nest made of aquatic vegetation, usually on the edge of lake/river • 35-50 eggs, 65 days to hatch • Female guards nest until hatching; removes vegetation to release young from nest

Nonavian-Reptiles

• Lepidosauria (tuataras, lizards, snakes) • Testudines (turtles) • Archosauria (crocodiles & birds)

Feathers

• Lightweight, yet strong • Hollow quill emerges from skin • Quill becomes shaft, which bears many barbs • Barbs contains many barbules that hook together • Barbs & barbules form a flat surface - the vane

What were some of the bonuses of the move to land?

• Major habitat diversity! • Tons of oxygen!

Sperm storage

• Mammals -- 1 day- 198 days (bats) • Birds -- 117 days • Reptiles -- 2555 days

Mating Systems (cont...)

• Many bird species are only socially (that is, in terms of overt pairing behavior) monogamous • Both males and females can seek Extra-Pair Copulations (EPCs) that may result in Extra-Pair Fertilizations (EPFs) and Extra-Pair Young (EPY) • From 0-75% of young may be extra-pair, depending on species

Mating Systems

• Monogamy • Pair bond is usually just for the breeding season • Often some extra-pair copulations • Polygamy • Polygyny - one male, multiple females • Polyandry - one female, multiple male

Metatheria: Marsupials

• Most in Australia, some in New Guinea & the Americas • One species native to U.S.: Virginia opossum • ~280 species • Pouch to hold developing young • Weak implantation in uterine wall • Embryo briefly receives nourishment from yolk sac & secretions in the uterus

Snakes

• No legs! • Unique anatomy makes their movement possible • Some are venomous • Some constrict prey • Lack tympanum. Can sense low frequency vibrations via jaw bones.

Single evolution of venom production:

• Occurred ~200mya • Common ancestor would have had both mandibular and maxillary toxin secreting glands • the maxillary glands were retained in snakes. • Mandibular glands were retained in Anguimorphs (gila monsters). • Both were retained in the Iguanian lizards.

Chytrid fungi (Phylum Chytridiomycota)

• One species (called "Bd" for short) infects the skin of amphibians • Causes chytridiomycosis - cells of outer skin layer develop hyperkeratosis (skin thickens)

Tuataras

• Only 2 living species (New Zealand) • Loss of habitat & predation by domestic and humanassociated species • Slow growth & low reproductive rates

Amphibia

• Order Gymnophiona (caecilians) • Order Urodela (salamanders) • Order Anura (frogs & toads)

Endothermy

• Origin independent from birds • Requires high metabolic ratesàhigh energy input

Order Sphenodonta

• Parietal eye • Protection from predators? • Circadian rhythms?

Class Amphibia - Characteristics

• Porous skin for respiration • Respiration by lungs, skin, and/ or gills • Dependent on moisture (including eggs)

Ectotherm Advantages & Limitations

• Require less energy (slower metabolism) • Need about 1/10 as much food as endotherm of the same size* • Cannot live in very cold climates (and need to hibernate in temperate zones in winter) • Depend primarily on environmental sources of heat • Basking, seeking shade, etc. • Debate about whether the dinosaurs were ecto- or endothermic

Bird sex

• Sex typically a "cloacal kiss" • However, some birds have true intromittent organs

Amphibia respiratory:

• Single-chambered lungs with an apical entrance • Many perform positive pressure breathing. • Gills are also a primary means of respiration for paedomorphic salamanders

Amniote Skin

• Skin with scales derived from epidermis • In general, amniotes have skin elaborations: scales, hair, feathers (all from keratin) • Skin dry (not moist). Less water lost via skin than amphibians

Amniote Jaws

• Skull fenestration (holes) allow bulkier muscles associated with jaw • Stronger jaws allow more pressure to be applied to prey • Muscular tongue, also • Expanded jaw muscles also allow wider gape

Amniote Clades

• Synapsida (mammals) • Diapsida ("reptiles") -Lepidosauria (tuataras, lizards, snakes) -Testudines (turtles) -Archosauria (crocodiles & birds)

Hair & Skin

• Thinner epidermis • Underlying, thicker dermis • Hair is a defining characteristic of mammals • Hair is composed of dead, keratin-packed epidermal cells

Amphibia have a ______ chambered heart

• Three-chambered heart • 2 atria & one ventricle • Red oxygenated, Blue deoxygenated, purple mixed • Separating the oxygenated blood from the deoxygenated blood circuit is not completed.

Class Aves - Paleognathae

• Tinamous (can fly a bit) • Ratites (ostrich, emu, kiwi, cassowary, rhea) *The moa, elephant bird, and emu/cassowaries are likely examples of convergent evolution of the large-body plan

Modified Limbs & Pelvic Girdle

• Upright rather than sprawling posture • Fore-aft rather than lateral gait • Well-developed calcaneus

Snake Predation by species

• Vipers (Viperidae) have mobile fangs (move into place to strike) • Elapid snakes have fixed fangs in the front of the mouth • Some snakes (including some Colubrids) have fangs in the back of the mouth, and grooved teeth guide venom into puncture wounds

Highlights:

• Whales and dolphins are a monophyletic group and their closest relative are hippos. • Sloths, armadillos and anteaters, aardvarks, tenrecs, dugongs, and elephants diverged from other Eutherian mammalian families 100mya • Bats closest relatives appear to be the families that include whales, rhinos, hippos, giraffes, cats, and pangolins-----not the rodents. • Split of main lineages occurred before Cretaceous-Tertiary extinction event about 65 million years ago. *but many orders evolved after

Adaptations for Flight

• Wings • Feathers • Pneumatized bones • Furcula (fused clavicle) • Keeled sternum & associated muscles • Cardio-pulmonary adaptations • Reduction in reproductive redundancies • No urinary bladder, uric acid excretion • Highly developed sensory perception

Amphibians as Indicators

• Worldwide declines in amphibian populations • Most severe in Australia, Central America, & Western United States

Costs of migration:

• energetic expense • risk • predation • human settlements or activity • weather • loss of territory

Lineage leading to amniotes:

• likely split from other tetrapods during a time we do not have many fossils • Show up in fossil record 306-312mya •Major extinction at Carboniferous Rainforest Collapse (CRC) 307mya • Reptiles flourished 307mya-65mya

Order Crocodilia (cont...)

• ~20 species • Large, heavy-bodied aquatic reptiles • Crocodiles, alligators, caimans, gharials • All carnivorous • Lie in wait, then ambush prey • Parental care in some species

Ardipithecus

•4.4 mya •Evolved to walk upright in forest habitat •Note splayed out toe •All toes face forward in other fully bipedal hominin species

Tetrapod Skeletal modifications

•Decoupling of pectoral girdle and skull to create a true neck. •bones from gill arches -> ears • lobed fins -> legs • Musculoskeletal adaptations for tongue protrusion

Cynodonts

•Enhanced jaw musculature & reduced number of jaw bones • Heterodont teeth • Secondary palate (bony roof of mouth - separates mouth & nasal cavity) • Loss of lumbar ribs (allows for greater agility)

Mammary Glands & Milk

•Evolution of mammary glands perhaps tied to evolution of diphyodont teeth • System of ducts surrounded by glandular tissue • Glandular tissue secretes milk

Bird Mating Systems

•If male parental care is not critical to survival of young (e.g., productive habitats), then there is no selective pressure on them to provide it, and they do not •Instead, males try to mate with as many females as possible

Snake Predation

•Prey swallowed whole • Constriction • Venom (multiple methods of injecting) • Teeth not suitable for cutting/chewing - just for holding prey • Parts of upper & lower jaws can move independently • Many aspects of feeding help the snake to avoid getting hurt while hunting