taxonomy and evolution

taxonomy

* science of classification
* founded by carolus linnaeus
* his taxa only included kingdom through species with domain added later

binomial nomenclature

* genus and species
* italicized, first letter capitalized for genus, lowercase species

taxa order

domain → kingdom → phyllum → class → order → family → genus → species

domains

bacteria, archaea, and eukarya

bacteria characteristics

* prokaryotic
* unicellular
* cell wall of peptidoglycan
* asexual reproduction
* both auto and heterotrophic
* shaped like rods, spheres, and spirals

archaea characteristics

* prokaryotic


* unicellular


* cell wall of not peptidoglycan


* asexual reproduction


* both auto and heterotrophic


* live in extreme environments

eukarya characteristics

* eukaryotic
* mostly multicellular
* if cell wall is present it is made of cellulose or chitin
* (a)sexual reproduction
* auto and heterotrophic

eukarya kingdoms

protista, fungi, plantae, animalia

protista characteristics

* mostly unicellular (things like seaweed aren’t)


* plant-like: autotrophic, cell wall of cellulose
* ex. euglena and seaweed
* fungi-like: heterotrophic, cell wall of chitin
* ex. slime molds
* animal-like: heterotrophic, no cell wall
* amoebas and parameciums

fungi characteristics

* mostly multicellular
* heterotrophic
* cell wall made of chitin
* ex. mushrooms and yeast

plantae characteristics

* multicellular
* autotrophic
* cell wall made of cellulose
* ex. cucumber

animalia characteristics

* multicellular


* no cell wall
* heterotrophic
* ex. cat

animalia phyllums

porifera, cnidaria, platyhelminthes, annelida, mollusca, arthropoda, chordata

porifera characteristics

* pore-bearing
* asymmetrical
* no movement (sessile)
* no mouth or anus
* porous for feeding
* ex. sea sponge

cnidaria characteristics

* comes from greek cnid (nettle)
* radial symmetry
* can move most of the time
* only mouth, no anus
* have stinging cells/primitive nervous system
* ex. jellyfish and corals

platyhelmenthes characteristics

* platy (flat) and helminth (worm)
* bilateral symmetry
* can move
* only mouth, no anus
* usually parasitic, flat bodied
* ex. leeches, tapeworms

annelida characteristics

* annelida means little rings
* bilateral symmetry
* can move
* both mouth and anus
* ringed/segmented worms
* ex. earthworms

mollusca characteristics

* latin moluscus (thin-shelled) from mollis (soft)
* bilateral symmetry
* can move
* both mouth and anus
* have muscular foot and a mantle (usually a shell)
* ex. octopuses, clams

arthropoda characteristics

* arthropod means jointed feet
* bilateral symmetry
* can move
* both mouth and anus
* jointed appendages, segmented body, and exoskeleton
* ex. spiders, butterflies, and lobsters

chordata characteristics

* latin chordatus (having a spine)
* bilateral symmetry
* can move
* both mouth and anus
* having a noto__chord__ - beginnings of a spine
* ex. cartilaginous fish, humans, reptiles

chordata classes

fish, amphibians, reptiles, birds, mammals

fish characteristics

* vertebrate
* no limbs, no nails/claws, no hair/fur
* two chambered heart
* external reproduction, gills, cold-blooded, swim bladder

amphibian characteristics

* vertebrate, tetrapod
* no claws/nails, no hair/fur
* three chambered heart
* external reproduction, simple lungs (and breathing via skin), cold-blooded, moist skin

reptile characteristics

* vertebrate, tetrapod, claws/nails
* no hair/fur
* usually three chambered heart
* internal reproduction (lays soft eggs), lungs, cold-blooded, keratinous scales

bird characteristics

* vertebrate, tetrapod, claws/nails
* no hair/fur
* four chambered heart
* internal reproduction (lays hard eggs), lungs, warm-blooded, wings with feathers

mammal characteristics

* vertebrate, tetrapod, claws/nails, hair/fur
* four chambered heart
* internal reproduction (live birth), lungs, warm-blooded, feed young with milk

human classification

* eukarya
* animalia
* chordata
* mammals
* primates - large brain, flat nails, specialized nerve endings, low rounded molars
* hominidae - great apes and humans, really smart
* homo - gay; also large cranial capacity, bipedal, hands, opposable thumbs, ability to use tools
* sapiens - humans

dichotomous key

questions or charts with two options that lead either to another question of the thing’s identity

theory of evolution

change in genetic makeup of a species or population over time

adaptation

a random difference in a trait leading an organism to become better suited for its environment over time

natural selection

* developed by charles darwin
* organisms best fit for their environment will survive and reproduce, passing on traits and changing the population

gradualism vs. punctuated equilibrium

* gradualism: slow and steady change
* punctuatated equilibrium: periods of no change followed by rapid change

convergent evolution vs. divergent evolution vs. adaptive radiation

* convergent evolution: organisms develop similar traits because of environmental similarities not a common ancestor


* divergent evolution: species share a common ancestor but diverge into different species
* adaptive radiation: one species evolves into many over time (type of d.e.)

evidence of evolution

fossils, anatomy, biochemistry, and embryology

relative vs. absolute dating

* relative: using a fossil’s position in the rock layers to label it older or younger
* absolute: using radioactive isotopes to find exact age of rock (usually carbon hence carbon dating)

transitional species

an intermediary fossil between two species

homologous structures

* a structure shared between two different species from common ancestry
* result of divergent evolution
* ex. tetrapod limbs

analogous structure

* structure shared because of similar environment not common ancestor
* convergent evolution
* ex. wings - bat and butterfly wings are different

vestigial structure

* a structure that no longer serves a purpose
* ex. appendixes in mammals

embryo development

* similarities can show a common ancestor
* ex. if it used to have gills, the embryo develops gills then loses them

biochemistry

using sequences of nucleic acids (DNA, RNA) or proteins to determine evolutionary relationships

cladogram vs. phylogenetic tree

* both diagrams showing evolutionary relationships between different species
* phylogenetic trees show time usually
* pretty much interchangeable