Bio readings18-26 chapter 23 plus pgs.777-809 Mar16began

What are the three cavities of the snail's coelom?

- one around the heart, -one around the reproductive organs, - and another that forms part of the kidney.

Identify characteristics that vary among diverse sponges.

- In some sponges the amoebocytes and collar cells are rigid. In other types of sponges the structures are composed of a flexible protein called spongin. -Sponges live singly or in clusters formed by budding. Budding is a form of asexual reproduction in which new sponges develop. -sponges can also reproduce sexually. Most sponges have both male and female gamete-producing structures in the same organism. -The 9,000 known species of sponges are diverse in shape, size, and color. -Some sponges consist of a single cylinder, while other sponges branch out irregularly over the seafloor or lake bottoms. - Some sponges, like Scypha, are quite small. Others can reach heights of 2 meters.

How does the life cycle of a sea star differ from other animals development into an adult form?

- Most animals begin development when the zygote divides repeatedly and forms a blastula. -Some animals, such as the sea star, first develop into a larva and then undergo metamorphosis. -Other animals develop directly into the adult form.(ex.humans)

endoskeleton

- The spines and plates are actually parts of a hard internal skeleton

Describe the digestive system of a roundworm.

- a complete digestive tract. -so has two openings, a mouth and an anus, at opposite ends of a continuous tube ( - Food travels only one way through a complete digestive tract .- the anterior region of the tract churns and mixes food with enzymes for digestion. -The posterior region absorbs nutrients from the digested food and disposes of wastes. - each part of the digestive tube is highly specialized for its particular function.

mantle

- an outgrowth of the body surface that drapes over the animal.

Describe the characteristics of echinoderms.

- bilateral - water vascular system, - tube feet that function inmotion

List 4 main threats to biodiversity

- endangerment and extinction of animals, fish, and plants has increased -pollution -habitat destruction by building of roads ,cities -new introduced species(non-native- brought in from other countries -overexploitation -

tube feet

- function in locomotion, feeding, and respiration

Bivalves

- include clams, oysters, mussels, and scallops. -They have hinged shells divided into two halves. - live in marine or freshwater environments. -- use their muscular feet for digging and anchoring in the mud or sand. - feed by pumping water over their gills and trapping food particles that are suspended in the water.

. What are three functions of the mantle in mollusks?

- produces the shell in mollusks such as clams and snails - functions in respiration, waste disposal, and sensory reception. -mantle cavity houses a gill. The gill extracts oxygen dissolved in the water and may also dispose of wastes.

Cephalopods

- squids and octopuses are faster and more agile than gastropods and bivalves. -The have external shell -most the shell is small and internal (as in squids) or missing altogether (as in octopuses). - marine predators, using beak-like jaws and a radula to crush or rip prey apart. - Their mouth is at the center of their foot, which is surrounded by 8-10 long tentacle-like arms that catch and hold prey.

3. Describe the appearance of a rotifer

- tiny animals. Most are smaller than many protists. -unique crown of cilia

niche

-An organisms habitat,food source, time of day they were active(feedingetc) and other important living conditions that can aid their survival over other species.

Describe the general characteristics of cnidarians.

-Have radial symmetry - presence of a gastrula stage during embryonic development.(gastrovascular cavity) - some basic tissues. For example, the outer layer of cells in hydras, called the epidermis, has protective and sensing functions. -The sensing functions include a nerve net, enables organism to respond to stimuli and coordinate its movements. -stinging capability

Compare and contrast the body structure of a hydra with that of a marine jelly

-Hydras are sessile(non moving -Marine Jellies are medusa body form and move freely in water -The hydra has a cylindrical body, about 3 cm long, -both lack a head. - Medusa have an an umbrella-shaped form with fringes of tentacles around the lower edge.

Explain the hypothesis of animals originating from colonial protists.

-Some animals formed that were multicellular organisms with specialized,interdependent(cells depend on each other to function together) cells and, in most cases, specialized tissues and organs. - One hypothesis is that these animals evolved from protists(one celled) that lived as colonies of cells . -Some of these colonies of identical cells may have, over time, formed hollow spherical colonies. (Bastula) -Gradually, some of these cells may have become specialized for certain functions. - As a result of this specialization, each cell was no longer independent.

Describe the general characteristics of sponges.

-Sponges (phylum Porifera) are the simplest animals. -sponges lack true tissues and organs. - different types of cells in a sponge are relatively unspecialized. -The body of most sponges consists of two layers of cells separated by a jelly-like material. - The outer layer of cells protects the interior of the sponge and also has many pores (holes) through which water can enter the sponge. -The inner layer of cells lines the central cavity of the sponge.

What are the three classes of cnidarians?

-The class Hydrozoa includes the hydras, some coral animals, and the large Portuguese man-of-war (the tentacles are actually colonies of polyps). -The class Scyphozoa includes the jellies. -The class Anthozoa includes the sea anemones and most coral animals.

Explain the difference between protostomes and deuterostomes.

-This difference in coelom(body cavity) development in early embryonic development

Describe 2 arguments for preserving biodiversity.

-Will affect our lives besides animals and plants lives - loss of future populattions/world crisis

vascular system

-a network of water-filled canals - branches into structures called tube feet

4 distinguishing characteristics of chordates?

-a notochord, -a dorsal hollow nerve cord, -gill slits, -and a post-anal tail.

nematocyst

-a type of capsule, contains a fine, coiled tubule that often has a poisonous barb at the end. When released, the barb from this type of nematocyst can penetrate and release poison into the prey.(can only do once)

Millipedes

-eat dead and decayed animals -have 2 sets of legs in each body segment -defend themself by curling in a ball and some species excrete poison, foul smelling if threatened

predator adaptations

-fastness, agility, camouflage,,acute senses of smell, hearing,sight, -adaptations of claws, fangs,stingers teeth can help them to catch prey

Describe the general characteristics of flatworms.

-flatworms have a digestive sac (gastrovascular cavity). The sac is highly branched, with a single mouth opening at one end. -bilaterally symmetrical animal has a distinct head, or anterior end, and tail, or posterior end. - It also has a back (dorsal) surface, a bottom (ventral) surface, and two side (lateral) surfaces. -In most bilateral animals the eyes and other sense organs are located up front, on the head. -how move- using cilia on its ventral surface, the planarian slides about in search of food. - It also has muscles that enable it to twist and turn. - The flatworm nervous system is also more complex and centralized than that of cnidarians. -A planarian's head has a pair of eyespots that detect light and side flaps that function mainly for smell.

Identify 4 approaches to conserving biodiversity

-focusing on hot spots wheresmall areas have high numbers of species thst could become extinct because not enough food(creating nature reserves -manage existing habitats or createnew areas for animals to live-protecting key habitat features like woodpeckers /promote growth of pine needed by bird that has been harmed by fires-deforestation

Describe the characteristics common to mollusks.

-have foot to help them move - mantle to produces the shell - mantle cavity houses a gill. (get oxygen,dispose waste) -radula- mouthlike characteristic

type decapod

-have ten legs(pincers/claws) -4 walking legs -most are marine but crayfish live in fresh water -2 main regions-abdomen and cephalothorax -exoskeleton very hard, made of limestone

bilateral symmetry

-identical mirror-image right and left sides. --has a distinct head, or anterior end, and tail, or posterior end. - has a back (dorsal) surface, a bottom (ventral) surface, and two side (lateral) surfaces. - the eyes and other sense organs are located up front, on the head.

1. Describe the function of the water vascular system of echinoderms.

-includes tube feet. - Each tube foot has a bulb that can pump water into and out of the foot. - When water is pumped out, the suction cup at the end of the foot contracts and grips the surface of objects. - A valve-like opening called the madreporite allows seawater to fill the water vascular system.

Gastropods

-make up the largest group of mollusks. - have a single shell that is often spiral-shaped. -live in freshwater, saltwater, and terrestrial environments. -land snails and slugs are the only mollusks that live on land.

pg 530 still reading 22 Crustaceans/type decapod

-most common aquatic arthropod -lobsters, crab, shrimp

. What distinguishes an animal from animal-like protists (protozoans)?

-mostly one celled eukaryote not animal(plant or fungus) Most animals take food into their bodies and digest it there, like you do. This system of nutrition, called ingestion, distinguishes animals from other heterotrophs, such as fungi, that digest food outside their bodies and then absorb the nutrients. -In addition, most animals have a digestive cavity, an internal sac or tube in which digestion occurs.

. Describe the function of cnidocytes and nematocysts.

-nematocysts penetrate and release poison into their prey to protect themselves,it is a capsule that contains a fine, coiled tubule. -A stinging capsule is located within each cnidocyte. to defend itself and capture prey -.Cnidocytes are especially abundant along the tentacles.

give an example for all 3 types of symbiotic relationships

-parasitism-mosquitoes live off your blood -mutualism-our intestinal bacteria aids us and the bacteria-they get home, food you get vitamin K needed for clotting of blood -commensalism- spider crab keeps seaweed on back as camouflage but the seaweed is not harmed or helped

prey adaptations

-retreat to safe areas, flee quickly, camouflage, -warning coloration- color stands out to warn animal not to eat them. mimicry-look like harmful other animal (ex hawk moth larvae can puff up head to look like poisonous snake - some plants have spines,thorns,or poisonous chemicals to stop attack by predator.

cnidocyte

-specialized stinging cells used for defense and capturing prey -Cnidocytes are especially abundant along the tentacles. - A stinging capsule is located within each cnidocyte.

biodiversity

-variety of life on Earth -variety of ecosystems and genetic variety among species

rotifers

. are tiny animals. Most are smaller than many protists. -multicellular animals with specialized organ systems. -rotifers have complete digestive tracts. -Rotifers get their name from their unique crown of cilia(hairlike tails that help them move). -Rotifers are common in freshwater environments such as ponds and even puddles. -This structure directs water into the rotifer's mouth where food particles can be filtered. - crown of cilia appears to rotate like a wheel (rotifer means "wheel-bearer").

Copy-Reading 23- Pg508-513 23.7,23.9 pg mollusks

.- have a muscular mass of tissue called a foot and a multifunctional structure called a mantle. - foot helps them move, but its structure is very different from a human foot. -very diverse, with about 150,000 known species

List four general characteristics of animals.

1. Animals are eukaryotic.(cells have nucleus plus cell membrane) 2. Animal cells lack cell walls. 3. Animals are multicellular.(many celled) 4. Animals are heterotrophs that ingest food.(eat food, digest it with tube,stomach,sac,etc.) ( fungi, that digest food outside their bodies and then absorb the nutrients.Also)

Describe three classes of flatworms

1. Planarians belong to the class Turbellaria. This group is mostly free-living (non-parasitic) and marine, but some planarians live in moist terrestrial environments.(ex.Flatworm) 2.Flukes (class Trematoda) are parasites—they are heterotrophs that absorb nutrients from the body fluids of a living host and in the process harm the host.(Ex.blood fluke called Schistosoma infects humans and causes a severe (blood fluke disease) 3Tapeworms (class Cestoidea) are also parasitic. Adult tapeworms such as Taenia solium, the pork tapeworm, live in the digestive tracts of vertebrates. The tapeworm itself has no digestive or circulatory system. Surrounded by partially digested food in their hosts' intestines, tapeworms absorb nutrients across their body surface. Each segment of the tapeworm contains reproductive organs that produce eggs.

1.What is a phylogenetic tree ? 2.Explore one hypothetical phylogenetic tree for animals.

1.This tree tracing the evolutionary history of animals is based on the best available data from fossils, molecular analysis, comparative anatomy, and comparisons of embryonic development 2. LOOK AT PG.516

metamorphosis

: complete change of body form in some animals from a larva to an adult(ex. larvae to caterpillar to butterfly)

coelom

A coelom is a fluid-filled body cavity that is completely lined by tissue (found in annelids -segmented worms)

closed circulatory system

Annelids have a closed circulatory system, where the blood remains contained within vessels. Nutrients, oxygen, and wastes diffuse in and out through the vessel walls.

2. Explain the significance of the phrase "Cambrian explosion."

Cambrian explosion, including genetic changes that made a greater diversity of body forms possible., but biologists still only have thories not fact on how this happened. Cambrian life did not evolve in the blink of an eye -the word explosion makes people think multicellular organisms were created quickly from protists but this not true it took millions of years.

Describe the three largest classes of mollusks.

Cephalopods, bivalves, Gastropods-info above

23.6- annelid's

Earthworms and other segmented worms, belong to the phylum Annelida, which means "little rings." Except for a distinct head and tail, an annelid's body segments are all very similar

acoelomates—

Flatworms are examples of acoelomates—animals that lack a body cavity.

overexploitation

Harvesting /hunting to such an extreme that some species may not survive

How did Gause's experiment with paramecium demonstrate competitive exclusion?

He had 2 species in separate areas first,and they both did well. Then he put them together and the stronger paramecium that collected their food faster were the ones to survive and reproduce not the other specie.

phyla

Major groups in animal category(ex. Invertebrates)

Explain the importance of biodiversity.

Many species are interconnected and depend on eachother for survival(food ,shelter etc) -if one species dies out whole ecosystem will be effected -organisms and ecosystems inspire us -we rely on many organisms for clothing ,food,medicine,shelter -more herbs have been identified to help people with cancer etc

medusa

Medusas (jellyfish-body form)move freely about in the water, transported by wind, water currents, and rhythmic contractions of the "umbrella."

open circulatory system

Most mollusks have an open circulatory system that includes a heart that pumps blood into vessels. -The blood vessels then open into chambers where the organs are bathed directly in blood. ( in contrast to an annelid's closed circulatory system, in which the blood is always contained in vessels-organs.)

23.5 roundworms

Most roundworms, or nematodes (phylum Nematoda), are small, cylindrical worms with somewhat pointed heads and tapered tails. -Roundworms range in length from less than 1 mm to more than 7 meters. The largest roundworms are parasites found in whales. - ---Like flatworms, roundworms have three tissue layers.

. Describe stages of the evolution of protists that may have led to the first animals.

One hypothesis is that animals evolved from protists that lived as colonies of cells. Some of these colonies of identical cells may have, over time, formed hollow spherical colonies.

Describe how zoned reserves may help conservation efforts.

Our interference like pollution, overbuilding, over hunting has caused this problem with us away from them they can reproduce and thrive naturally.

Reading 21/pgs. 502-507/23.4 flatworms (phylum Platyhelminthes [plat i HEL minth ez]).

Planarians are examples of the mostly small, leaflike or ribbonlike flatworms - flatworms, like most other animals, are bilaterally symmetrical

radial symmetry

Radial symmetry is the regular arrangement of body parts around a central axis. ..(circular form like squid)

List the diverse habitats of roundworms.

Roundworms live almost every place there is rotting organic matter. -decomposers in soil and on the bottom of lakes and oceans. -Other roundworms thrive as parasites in the moist tissues of plants and in the body fluids and tissues of animals.

2. Compare and contrast sea cucumbers with sea stars.

Sea star- -arms connect to the central disk,hundreds of tiny tube feet on the bottom of each ray, -The vascular system is also filled with sea water to allow them to move, -light sensitive organ called an eyespot( can detect light and its general direction) -,can regenerate legs, eat barnacles, snails, sea urchins, clams, and mussels. Sea cucumbers- five rows of tube feet running lengthwise - mouth surrounded by tentacles - tubed feet. -the vascular system is not filled with sea water.( special body fluid instead) -eat plankton and other organic matter -(throw out) all of its internal organs, scares off or satisfies predators. -can then grow another set of internal organs.

23.8 same reading 23 Echinoderms

Sea urchins, sea stars, and sea cucumbers are all slow - lack body segments - most haveexternal parts of the animal radiate from the center like spokes of a wheel.

Compare and contrast three different classes of echinoderms.

Sea urchins,-disk,shaped not 5 rays,tube feet sea stars-5 rays(like legs), no tube feet sea cucumbers- leathery covering allows them to move on sea floor ,no tube feet,reproduce by shedding eggs and sperm into water to fertilize

Compare and contrast body systems of various invertebrates.

Sponges have no tissues, no nerve control(ex.lung tissue) Cnidarians have a radial symmetry.Fluids give body shape and have a nerve net since it has no spinal cord to send messages through body Starfish and worms have a bilateral symmetry, primitive brain and nerve cords.

Explain the meaning of the phrase "Cambrian explosion."

The burst of animal diversity from simple celled protists to multicellular animals with complex digestive tracts to digest food.

Cambrian period.

The first period of the Paleozoic Era, from about 540 to 505 million years ago. During this time warm seas and desert land areas were widespread, and animal life diversified rapidly during what is known as the Cambrian Explosion

endoskeleton

The internal supporting framework of humans and other vertebrates, usually made of bone.

Compare and contrast vertebrates and invertebrates.

The majority of aquatic invertebrate species live in marine waters. While Vertebrates, are on landbut also live in marine and freshwater habitats. There are at least 19 known invertebrate species. but there are about 35 major groups (phyla). of animals in total with backbones or not)

History of how complex animals evolved from first simpler forms of life.

The origin of ingestion (eating) as a mode of nutrition was an important milestone in the beginning of animal life evolving from simple protists. - Diverse forms of animals evolved, differing partly in their feeding adaptations. - Early animals populated the oceans, then fresh water, and eventually land

2. Give an example of roundworms interacting with other organisms. .

These worms are important decomposers in soil and on the bottom of lakes and oceans. Other roundworms thrive as parasites in the moist tissues of plants and in the body fluids and tissues of animals.

How are vertebrate and invertebrate chordates different?

Vertebrates- -hinged jaw - cannot eat eat large animals like snake -have endoskeleton to support their body -kave nerve cord ,backbone, vertebrae Invertebrate- - no backbone -no nerve cord or notochord,(tunicats, lancelets-marine animals-look like sacs attached to rocks),no endo skeleton,

polyp

a cylindrical body with tentacles radiating from one end. Animals with a polyp body form are mostly sessile(grounded in one place) like a the cnidarians -hydra.

gastrovascular cavity

a digestive sac c - food enters through the mouth and is digested in the cavity. - Undigested food and other wastes exit back through the mouth. -This ability of the cavity to function as a circulatory (or vascular) - (gastro- means "belly" or "gut"). -Fluid in the cavity provides body support and helps give cnidarians their shape, much like water in a balloon.

notochord

a flexible rod-shaped body found in embryos of all chordates. -composed of cells derived from the mesoderm(middle of skin layer)

tetrapod

a four-footed animal, especially a member of a group that includes all vertebrates higher than fishes.

sessile

adult sponges are anchored in place

ganglia

along the nerve cells there are clusters ofthese nerve cell bodies

predation

an interaction where one animal eats another one

vertebrate:

animal with a backbone(ex.insect,snake,humans,mammals)

conservation biology

applying biology knowledge to counter loss of biodiversity.

zoned reserve

areas of land that are left undisturbed by humans

buffer zone

areas that surround zoned reservesand are minimally impacted by humans

molting

as an arthropod grows it must shed its old skeleton and secrete a larger one.

List three methods of sponge reproduction.

asexually-budding sexually regenerating- Small fragments of a sponge body can grow into an entire new sponge.

Insects

beetles,ants,grasshoppers,butterflies,dragonflies,

mutualism

both organisms benefit from symbiotic relationship

Reading 19-pg 514-19 3/17 / reading Cambrian explosion:

burst of diverse animal species originating during the Cambrian period

causes and possible results of interspecific competition

causes- drought or other climate issue leads to less resource, more predators for that food source because another source is gone results- animal forms adaptations to survive, one specie dies out, an the increase of the population density of one specie

amoebocyte

cells that pick up food from the collar cells, digest it, and carry the nutrients to other cells. Amoebocytes also transport oxygen, dispose of wastes, and can change into other cell types, such as support structures.

tracheae

chitlin lined tubes that lead from the internal parts of the body to the outer parts -they allow the exchange of Co2 and oxygen through the spiracles.

symbiotic relationship

close interaction between 2 species

Reading 20 still-pg.499- 501 /23.3 cnidarian

cnidarians include the jellies (jellyfishes-PORTUGUESE MAN OF WAR), hydra, sea anemones, and coral animals -have radial symmetry and tentacles with stinging cells.

COPYreading 25-pg777-780 35.4- 3/25 interspecific competition

competition between 2 species relying on same resource -

sustainable development

developing natural resources sothey can renew themselves afor the future

23.1-RDG 18- 3/16 blastula:

embryonic stage in most animals consisting of a single layer of cells surrounding a hollow cavity(forms during meiosis when gametes(sex cells)fertilize)

gastrula:

emybronic stage following the blastula that has an inner and outer cell layer(forms during mitosis)

carapace

exoskeleton that covers the back of the cephalothorax forms the shield(carapace)

compound eyes

eyes with many lenses unlike us we have one lens

exoskeleton

hard exoskeleton (cannot grow)

radial symmetry

has body parts arranged like pieces of a pie around an imaginary central axis.(circular)

complete digestive tract

has two openings, a mouth and an anus, at opposite ends of a continuous tube -. Food travels only one way through a complete digestive tract. In animals with a digest

spiracles

holes in the exoskeleton

larva:

immature form of an animal that looks different from the adult form

4. Which invertebrate phyla have an open circulatory system?

in an open circulatory system (mollusks,invertebrates,insects) blood fills body cavities unlike in a closed system. -The open circulatory system is a system in which a fluid in a cavity called the hemocoel bathes the inside(why called open) of organs directly with oxygen and nutrients and there is no distinction between blood and interstitial fluid; this combined fluid is called hemolymph. - closed system (ex.fish,humans)blood circulates around organs(why called closed no blood in organ) .

24.1 /24.3-Reading 22 pg 524-27 +530-531 arthropod

invertebrates characterized by their segmented bodies, jointed appendages, and exoskeletons

3. Explain the difference between the blastula and gastrula stages of development in most animals.

like sea star development-Usually the blastula consists of a single layer of cells surrounding a hollow cavity. Later, in many animals, one side of the blastula folds inward, forming an embryonic stage called a gastrula. (Forms in Meiosis) The gastrula has both an outer and an inner cell layer.(Forms in Mitosis)

crustaceans

lobsters,shrimp ,crayfish, crab,barnacles,large claws and or appendages

barnacles

marine rustaceans that secrete calcium carbonate shells where they live -cover rocks, piers ,ships ,whales skin

Reading 20 /pg.497-501/23.2 and READING 21 /23.3 sponge:

member of a group of animals that lack true tissues and organs

invertebrate:

member of a group of animals without a backbone (ex.worm,insect, Sea anemone,Many marine animals)

thorax

midsection of an arthropod (legs, wings, etc.)

myriapods

millipedes,centipedes,body segments,each body segment has pair of legs, more legs than insects -live in humid environments under rocks,in soil

hard mandibles

mouthparts closest to mouth bite ,grind food

chordates

numerous animals having at some stage of development a dorsal nerve cord, a notochord, and gill slits including all vertebrates, the hagfishes, and certain marine animals such as the lancelets and the tunicates.

parasitism

one animal,the parasite, gets its food from its host(ex tapeworm-sits in intestine gets bigger and bigger eating off hosts food eaten)

commensalism

one organism benefits but the other one is not harmed or helped

bilateral symmetry

organism or part can be divided into two equal halves(Ex worm)

collar cell

outer and inner layers of cells in sponges.They have flagella which arte like tails to help them move.??Check

jointed appendages

points where an organism can bend

What are the general characteristics of vertebrates?

presence of the spinal cords, vertebrae and notochords.

What are two characteristics common to all cnidarians?

radial symmetry and tentacles with stinging cells

How is a roundworm's digestive system different from that of a flatworm?

roundworm= a complete digestive tract. Flatworm= have a digestive sac (gastrovascular cavity). The sac is highly branched, with a single mouth opening at one end.

3. Describe two characteristics that vary widely in the sponge phylum.

size,shape, rigidity

3. Describe how a mollusk uses its radula for feeding

slides back and forth like a garden rake, scraping and scooping algae off rocks.

copepods

small like krill big role in food chains in marine and freshwater feed on bacteriaplankton,less than 2mm main source of food for small fish,cod

isopods

small marine crustacean :wood lice: pill bugs ,found under wet or rotting leaves

arachnids

spiders.scorpions,mites,ticks

What are the 4 subgroups of tetrapods(vertebrates)?

tetrapod=four footed -mammals, crocodiles( lizards,snakes) birds,turtles,amphibians-pg 544

deuterostomes

the coelom(body cavity) forms from a portion of the digestive tube of the early embryo. -echinoderms, cordates,humans

protostomes

the coelom(body cavity) forms from solid masses of cells in the embryo -annelids, mollusks,arthropods

chitin

the exoskeleton has layers of protein mixed with polysaccharides

pseudocoelom

the pseudocoelom of roundworms is a fluid-filled body cavity in direct contact with the digestive tract.

vertebrae

the sections of the vertebrate(backbone) that enclose the nerve cord.

3. Explain why biologists consider the phylogenetic tree in Figure 23-25 to be hypothetical.

the tree was created to stimulate further research,new information information and discussion, but the info on the tree is not known for sure because scientists lack factual knowledge about the fossils in this time period.

How barnacles feed

their appendages they use to sweep smallinvertebrates and organic particles toward their mouthparts inside their shells

radula.

unique rasping organ - An aquatic snail's radula extends from the mouth and slides back and forth like a garden rake, scraping and scooping algae off rocks. -Other mollusks use their radulas to drill through shells to prey on other mollusks.

competitive exclusion

where one species succeeds over another for same resource