zoo prime

Total number of animal species

Total number of animal species

1.5 million

Number of freshwater fish species

15,000

Number of total fish species

32,000

Estimated number of invertebrates

30 million

Body plan determined by

constraints imposed by ancestral body plan demands and requirements of current lifestyle

General example of shared ancestry

mammalian guts thylacine vs dog dentition (same function, convergent evolution, but noticeably different; thylacine is marsupial and dog is mammal)

panda constrained by body plan

Pandas have carnivore

metamerism

repeated

5 levels of organisational complexity

protoplasmic cellular cell

protoplasmic complexity

all function contained within single cell eukaryote or prokaryote

cellular

level complexity

cell tissue level complexity

cells aggregate into specialised tissues or layers

tissue

organ level complexity

organ system

level complexity

4 types of symmetry

asymmetry spherical symmetry (probably in water) radial symmetry bilateral symmetry (probably has locomotion)

two types of early cellular cleavage

radial cleavage

two types of early cellular development

regulative

man who proposed hierarchical classification system

Carl Linnaeus

number of animal phyla

35 each is monophyletic (all animals within a phyla evolved from a common ancestor)

when life evolved on earth

4 billion years ago appearance of atmospheric oxygen + photosynthesis (which added more O2) made multicellular life possible

when animals evolved

600 million years ago

evidence that all life is related

same genetic code used by all life (RNA and DNA)

unicellular eukaryotes

aka protozoa 30 clades, 64,000 species small size and varied breeding systems found everywhere with water

eukaryotic cell characteristics

specialised organelles nucleus with DNA and chromosomes mitochondria golgi apparatus plastids for photosyntehsis vacuoles for osmoregulation and storage allows for greater size and metabolic efficiency and makes multicellularity possible

3 types of eukaryotic cell locomotion

pseudopodia, cilia or flagella

3 eukaryotic cell body forms

ciliate, flagellate, and ameba

implications of locomotor organelles

respiration, feeding, and size

number of times multicellularity evolved

25 times

metazoa

any multicellular animal

choanoflagellates

form circular colonies in water flagella and cilia sucks water into body closely related to animals

phylum porifera

sponges four classes 5,000 species mostly marine, shallow to deep sea many commensal (grow on other things) spicules and chemicals to deter predation no circulatory system; need water to flow through them, so only grow tall and thin shape (so that there's enough inner surface area compared to volume) cells differentiated for various functions (but only 4 cell types) radial symmetry or none skeleton made of collagen, calcareous filaments or spicules (which double as predator defense) no digestive system; food captured by choanocytes and eat by phagocytosis no nervous system, although electrical signalling in glass sponges sponges DO have circulatory structure, but constrained by rates of metabolism and waste product produced (so more commonly found in cold water; lower metabolism so lower waste) reproduce by fragmentation and budding monoecious

3 types of sponge structure

asconoid = small, cylindrical water flow syconoid = medium, pouches on inside that add surface area leuconoid = large, highest inner surface area to suck water through

sponge main hole name

osculum

small sponge pore name

ostia

monoecious

male and female sex cells in one individual

phylum cnidaria

simple polyp (tree shape) or medusoid (jellyfish shape) body form often form colonial organisms includes corals, jellyfish, sea anemones, and hydrozoans all are active predators first animals that can move only predator of jellyfish is the Mola mola (aka sunfish) have tissue

phylum cnidaria, class hydrozoa

solitary or colonial polyp structure hydras, man

phylum cnidaria, class scyphozoa

includes typical medusoid jellyfish lots of nematocysts have gastric pouches (gut throughout the whole body) means no need for circulatory system to disperse nutrients mouth = manubreum, frilly thing that wraps around prey and pulls prey in

phylum cnidaria, class cubozoa

box jellyfish well formed eyes and other sense organs

phylum cnidaria, class anthozoa

corals and anemones individual polyps or large colonies

endoderm vs ectoderm vs mesoderm formation

endoderm = forms gut, liver ectoderm = forms skin, eyes, external tissues mesoderm = muscles and circulatory system

acoelomate vs pseudocoelomate vs coelomate

acoelomate = no circulatory system; materials slosh around, move through diffusion pseudocoelomate = mesoderm next to ectoderm, no mesoderm around gut coelomate = cavity inside mesoderm; mesoderm wrapped around gut = rapid transport of material from gut. coelom evolved thrice, once in mollusca, once in arthropoda, and once in deuterostome (chordates ish)

protostomia vs deuterostomia

protostomia = spiral mosaic cleavage, blastopore forms mouth, diverse group of animals with varied body plans deuterostomia = determinate regulative cleavage, blastopore forms anus, internal skeleton in echinoderms and chordates

phylum platyhelminthes

flatworms, tapeworms, and flukes triploblastic, acoelomate, bilateral (which means that they move) marine, freshwater, and moist terrestrial habitats no specialised circulatory and respiratory system (implications for size and shape; can't get big but can be long and thin) turbellarians mostly free

phylum platyhelminthes, class trematoda

parasitic flatworms

phylum mollusca

mollusks include snails, slugs, mussels, scallops, squid, octopus, nautilus, chitons, nudibranch seven classes; 50,000 extant species mostly aquatic but some terrestrial limited by humidity and calcium (for shell) large variety of feeding mechanisms bilaterial well

phylum mollusca functions of body regions

visceral mass = digestion, reproduction, circulation head/foot = orientation, feeding, locomotion shell = protection mantle = shell secretion, respiration by lung/gills increasingly important in larger molluscs altering proportions of different body parts = makes different lifestyles possible

phylum mollusca class monoplacophora

metameric segmentation; serial repetition of gills, retractor muscles, etc (so only need 1 set of genes for a segment and another set of genes for how many segments you need)

phylum mollusca class polyplacophora

chitons; 3mm to 40cm long (big enough to be erosive) and scrape algae from rocks using radulla have metameric segmentation very efficient respiratory system; ciliated gills, constantly beating and sucking water in, then pushing it along the inside of the body; allows them to get very big

phylum mollusca class gastropoda

snails most diverse, 40,000 extant and 15,000 estinct shell present or absent slow

phylum mollusca, class bivalvia

clams reduced head and foot because they're sedentary very large gill and mantle cavity that allows for lots of filter feeding and respiration, which means they can be very large (ex: giant clams) open (low pressure) circulation through visceral mass

phylum mollusca class cephalopoda

nautilus, squid, cuttlefish, octopus physiological equivalent to chordate group active predators all marine foot divided into multiple tentacles

squid (cephalopod) form and function

fast movement: high metabolic rate, efficient respiration (gills and active circulation of water by mantle) and digestion (aided by beak); closed, high pressure circulation, 3 hearts (one under each gill, and one primary heart) coordination: well

phylum annelida

earthworms, freshwater worms, leeches 15,000 species marine, freshwater, and terrestrial variety of feeding mechanisms; free living bottomfeeders, burrowers, filter feeders, sediment feeders, etc organ

annelid form and function

complete gut (mouth and anus): higher

leech (phylum annelida) terrestrial adaptation

rapid evaporation due to high surface/volume ratio (they're long and thin) AND use body for respiratory exchange

ecdysozoa

8 phyla all excrete cuticle (allows them structure, flexibility, reduces water loss, muscle attachment for locomotion) moult outer cuticle (ecdysis = molting) two body plans: worm

lophotrochozoa

18 phyla some have lophophore for feeding some have trochophore larva spiral cleavage of embryo

phylum nematoda

roundworms collagenous cuticle (contains hydrostatic pressure exerted by fluid in pseudocoelom) longitudinal muscles, no circular muscles hydrostatic skeleton no segmentation free

phylum nematomorpha

horsehair worms parasitic larvae, free

panarthropoda

includes onychophora, tardigrada, and arthropoda all have reduction of coelom (no hydrostatic skeleton), ventrolateral appendages, open circulatory system (works because they are so small; oxygen can just diffuse into their tissue, don't need oxygen to be delivered places), and paired walking appendages

phylum onychophora

worm

phylum tardigrada

water bears lobopods (unjointed limbs) buccal stylets as mouth no thorax because they don't need it, unlike arthropod or onychophoran have segmented nervous system, nerves in each leg, and anterior brain

phylum arthropoda

bilateral symmetry coelomate moulting cuticle exoskeleton jointed legs and segmentation; efficient locomotion specialised appendages like wings, mouth parts, jointed legs, claws most abundant group of animals on earth wide range of sizes, mm to meters highly developed sensory organs open circulatory system

phylum arthropoda, subphylum trilobita

marine taxa extinct for 250 million years, lived during cambrian and ordovician bottom dwellers and scavengers most have eyes

phylum arthropoda, subphylum chelicerata

contains spider class no mandibles or antennae have chelicerae (mouth claws) 1 pair of pedipalps (push food into mouth) and 4 pairs of walking legs

phylum arthropoda, class merostomata

giant water scorpions and horseshoe crabs have regular arthropod setup but with big shell

phylum arthropoda, class arachnida

spiders, scorpions, ticks, mites 80,000 species described many are venomous with poison fangs adapted from chelicerae many eyes pedipalps to capture prey (big pincers in scorpions), chelicerata to rip apart

phylum arthropoda, class arachnida, order acari

ticks and mites mouth parts on captiulum, more external than other orders within arachnida some are free living, most are parasites

phylum arthropoda, subphylum myriapoda

centipedes, millipedes have mandible jaws like crustaceans and hexapods, used for biting, cutting, holding food, and chewing (more variable than chelicerata) all have antennae over 13,000 species first animals on land two tagmata (head and trunk) mouthparts: mandible and one (millipedes) or two (centipedes) pairs of maxillae legs are uniramous, 10 to 750 pairs simple eyes

phylum anthropoda, subphylum myriapoda, class chilopoda

centipedes predatory each segment has one pair of legs maxillipeds on first segment are modified to venom fangs pair of simple eyes

phylum anthropoda, subphylum myriapoda, class diplopoda

millipedes cylindrical bodies antenna for feeling mandible mouthpart

mandibulata hypothesis

groups together the three arthropod subphyla with mandibles (chewing mouthparts/jaws): myriapoda, hexapoda and crustacea

phylum arthropoda, subphylum crustacea

lobsters, crayfish, shrimp, barnacles 67,000 described species two pairs of antennae head has pair of mandibles and two pairs of maxillae to form jaw one pair of appendages on each additional segment some biramous appendages (ex: antennae) extremely segmented

phylum arthropoda, class malacostraca

woodlice, pill bugs flat aquatic and land forms includes decapoda: lobsters, shrimp, crabs. 5 pairs legs, in crabs first pair of walking legs forms pincers (chelae)

phylum arthropoda, subphylum hexapoda

6 legs tagmata = head, thorax, abdomen mandibulate, closest relatives are crustacea single pair of antennae compound eyes two classes: entognatha and insecta

phylum arthropoda, subphylum hexapoda, class insecta

bases of mouth parts visible have mouthpart including labrum, mandibles, maxillae, labium, hypopharynx that all aid eating have brain (collection of ganglia) size is restricted because their respiration is not super efficient, used to be larger but lower atmospheric oxygen now = smaller insects feeding determined by mouthparts: chewing or sucking

phylum arthropoda, subphylum hexapoda, class insecta, superorder holometabola

butterflies, ants, bees, wasps, beetles, fleas, flies, moths undergo complete metamorphosis inlcudes 88% of all insects

phylum arthropoda, subphylum hexapoda, class insecta, superorder hemipterodea

stoneflies, stickbugs, mantids, cockroaches, lice externally developing wings don't go through metamorphosis; go through nymph stages instead

phylum echinodermata

starfish all have calcareous skeleton; spiny endoskeleton that acts like an exoskeleton. Made of dermal calcareous ossicles called stereom, covered by ciliated epidermis unique water vascular system; coelomic, extends from body surface as tentacle projections filled with fluid. Usually have opening to exterior called madreporite pentaradial (five

phylum echinodermata class asteroidea

starfish mouth on underside of oral surface, anus on top abulacrum runs from mouth to tip of each arm. papulae along each ambulacral groove, function in respiration; the gills of the sea star two coelomic cavities; coelom with papulae and water vascular system with tube feet can regenerate arms

phylum echinodermata class ophiuroidea

shaped like a starfish but with thin wobbly arms arms are thin ambulacral groove is closed and coated with ossicles tube feet lack suckers

phylum echinodermata class echinoidea

spiky sea urchins lack arms but still have five

phylum chordata

characteristics they share with inverts: bilateral symmetry tube

characteristics unique to chordates (important): notochord (flexible rod, fluid

filled cells, attached to muscles. in humans, is fluid spongy tissue within spine) dorsal tubular nerve cord (in inverts, nerve cord is ventral underneath digestive system and is solid, so this is unique) pharyngeal pouches or slits (form gills or pharyngeal grooves. Used as filter

phylum chordata subphylum urochordata

sea squirts adults only retain 2 chordate features, retain pharyngeal gill slits and endostyle (but have all 5 as larvae)

phylum chordata subphylum cephalochordata

amphioxus features that suggest the vertebrate body plan; might be the ancestral chordate segmented muscle blocks down either side closed circulation but no heart; its movement moves materials

phylum chordata subphylum vertebrata

earliest vertebrates modifications of skeletal structures and muscles permitted increased speed and mobility segmented body muscles (myomeres) changed from v

agnathans

jawless fish (paraphyletic group) includes lambrey

gnathostome fishes

cartilaginous fishes (chondrichthyes). ex: sharks rays. gills and gill slits. bony fishes (osteichthyes), dominant ones today. 2 major clades: ray

actinopterygii

ray

sarcopterygii

lobe

fish tails and buoyancy

lunfish have diphycercal tail perch have homocercal tail (normal fish tail)

fish buoyancy

sharks have lipid called squalene that's lighter than water and makes them more buoyant. Also, fins are angled up to keep them from sinking. swim bladder is a gas

fish respiration

water flow is opposite to blood flow, called countercurrent flow, maximizes the exchange of gases very efficient; can remove up to 85% of oxygen from water passing over gills some active fishes use ram ventilation; swimming with mouth open and forward movement is enough to force water across gills, but will suffocate and die if they stop swimming

characteristics necessary for the origin of tetrapods

air

live in terrestrial environment; need special adaptations stronger bones because air is a less buoyant medium muscles to elevate the head, support the body in air stronger shoulder and hip girdles modified ear structure longer snout

amphibian adaptations

mucous covered skin to avoiddesiccation and UV light damage capillary network underneath skin, can obtain oxygen. lungless salamanders only use skin for oxygen, called "buccopharyngeal respiration" exaptation features = features that evolved for a different reason. used to have air

phylum chordata class amphibia order apoda

called caecilians looks like a worm ectotherms eggs easily desiccate; must be laid in moist terrestrial places

phylum chordata class amphibia order caudata

salamanders most have aquatic larvae and terrestrial adults internal fertilization in most species that are completely terrestrial lay their eggs in small clusters in moist places respiration through gills, lungs, both or neither. vascular nets in skin that exchange CO2 and carbon dioxide