ray finned fish, birds

1. systematics

2. phylogenetic systematics

1. -grouping animals based on how similar they are and the unique features they share.

2 -groups species according to common ancestor and its decendants

-comes from phylogeny: evoloutionary history of a group

morphology

-study of form

-helps us classify

-when animals are grouped, this is how we name the group

-darwin

-propsed 4 postulates about the origins of species

-individuals within species vary

-some of the variations found in populations are passed on to offspring

-every generation more offspring are produced than can survive

-survival and reproduction success is not random

-difference between survival or reporudctive success with specific phenotypes compared to other phenotypes

-phenotype: refers to all physical and behavioral traits displayed by an organism

-genotype:  phenotype depends on this, refers to the gene passed on

-darwin's explanation of degree to which an organism contributes to further generations.

-maintains oldest rock layer on bottom

-any layer that cross cuts other layers are the youngest

-4 specific traits

-notochord: support for animal

-pharyngeal slits: gills

-dorsal hollow nerve cord: above notochord, becomes brain and spinal cord.

-postanal tail

-tissue composed of a matrix of collagen fibers impregnated with calcium phosphate and hydroxyl icon crystals.

-first known vertebrates

-many extinct, most ancestors of living fish

-primitive

-Cambrian

-early silurian

-first jawed fish

-'spiny fish'

-not ancestors, but similar to bony fish

-chondrichthyes

-sarcoterygii

-actinoptergii

-cartiliginous fish

-subclasses

-elasmobranchii

-holocephali

-most successful vertebrate class.

-one of two groups of bony fish (osteichthyes)

-no one knows the ancestor

-silurian period

-evolved in fresh water

-overlapping scales, airsac, internal skeleton

-lobe finned fish

-direct ancetors of tetrapods

-2 fish: lungfish and coelacanths

-devonian

-direct ancestor of amphibians

-ray finned fish

-amphibians and reptiles

-all extinct except subclass lissamphibia (frogs, toads, salamanders)

-had labrinthine folding teeth on cross section

-old amphibians

-oldest member: ichythyostega

-becomes ancestor of all reptiles, birds, and mammals

-group reptilia

-living and extinct turtles

-mode of development where eggs are laid

-sphrenodon

-komodo dragon

-largest lizard

-group of extinct marine reptiles

-plesiosaur

-ancestor to crocs and virds

-extinct pterosaurs and dinos

-flying reptiles

subclass synapsida

-many extinct forms

-left impressive fossil record with great diversity

-pelycosaurs

-large sail on back

-'aves'

-endothermy (warm blooded)

-of group aves

-earliest winged vertebrates

-archaeopteryx

-all other birds

-very diverse

-egg laying mammals

-includes echidna

-subclass of mammals

-includes marsupial class metatheria

-includes placetal group (most common) eutheria class

-giving birth to live offspring

-eggs retained in body, hatch inside, and then are born live.

-monogamy is one male and one female

-polygamy where males and females have more than one mate

-polygyny: one male and many females

-polyandy: one female and many males

-3%

-matriarchal group: group led by female

-patriachal group: group led by male

-movements by animals as they approach sexual maturity

-often pushed out by parents

-life long migration back to breeding grounds where they were born

-salmons do this

reptiles fossil record?

-carboniferous

-first animals in fossil record

-oldest species very different than species today

-study of developement

-helps us classify

-similarities and differences in organisms, organized into

-homologous structures (similar structures)

-analogous structures (similar environment)

-comparitive studies of rna and dna

-helps us classify

-jurassic

-late triassic

placadermi

-late silurian

-extinct in devonian

-bone plates

-not ancestors, but similar to jawless fish

-fresh and salt water

elasmobranchii

-sharks, rays, skates.

-uncovered gills

-silurian
-subclass of chondrichthyes

-holocephali

-covered gills

-rat fishes

-evolved independently of other chondricthyes

-not abundent

-subclass of chondrichthyes

-jawless fish

-includes subclass myxini (living hagfishes)

-includes subclass cephalaspidomphi (living lamphreys)