Lecture 12 - Classification of living things

this is talking about how anthropology classifies all the living things into different groups.

System of Classification

all animals placed into certain categories based on structural similarities that reflect adaptation & evolutionary descent.

taxonomy

establishing the rules of classification

Taxon =

category

taxa =

categories

Nom =

name

taxonomy means…

category names

who was the father of taxonomy, that devised a system of classification for all plants and animals based on physical similarities?

Linnaeus

what was the traditional 4 nested categories in Linnaean system?

• class

• order

• genus

• species

what groups were added later to the linnaean system to make it 7?

• kingdom

• phylum

• family

seven basic categories

• kingdom (kings)

• Phylum (play)

• Class (Chess)

• Order (On)

• Family (Fat)

• Genus (Green)

• Species (Squares)

Species

only organisms that can interbreed and produce fertile offspring

how did Linnaeus build his taxonomy?

first classification scheme based on physical similarities

• similarities in body function and ontogeny or similarities in bodily growth

What Sequence of Bodily Structure?

“G” Cow “H” C would be classified as the same species - have identical body structures

Cow and Horse are different species because - do not have same body structure.

Body Structure

Cows & Horse = closely related to each other

Chicken lays eggs & does not have mammary glands

• they differ in their reproduction

Sequence of Bodily Growth

at the time of birth - look like smaller versions of the adults

• basic similarities - good starting point

• they must reflect common descent of organisms

Phylogeny

Evo. history & relationship of an organism/group of organisms

what are examples of forelimbs of terrestrial air breathing vertebrates?

• amphibians

• lizards

• birds

• humans

similar and have a resemblance, all are similar in number

Homologies

traits shared by multiple species through inheritance form a common ancestor

homologies are….

reliable indicators of evolutionary relationships

• traits may differ in form & function

what has been examined to have many similar structural similarities as humans?

Whale Skeletons

analogous structures

do not reflect a common ancestry

how are bats and butterfly wings compared?

• bats are mammals → internal Skeletons, central nervous system, four limbs

Dolphins (mammals) and Sharks (cartilaginous fish) are an example of?

analogous structures

developed out of similar need in a similar environment

analogies

• traits are similar in shape

• appearance and function (came from different ancestral condition)

homoplasy

Similar physical characteristics in unrelated organism

interpretations and devising classifications

• refelct common evolutionary descent

• evolutionary biologists concentrate on the homologies

• treat analogies as extraneous noise

Primitive (ancestral traits)

homologies or traits shared through remote ancestry

derived or modified traits

more useful for classification

modified from the ancestral condition

only mammals have fur, what characteristics should be used to devise classifications?

• characteristics that reflect more specific evolutionary adaptations

• both mammals, should be done only when shows shared derived characteristics

cladistics

emphasis on identification & application of shared derived characteristics underscores a contemporary approach to taxonomy.

produces - clades

Clades (Cladograms)

show evolutionary relationships based on shared characteristics

& INCLUDES COMMON ANCESTOR AND ALL DESCENDANTS

Phylogeny

• evolutionary tree - chart that hypothesizes likely ancestor-descendant relationships shown relative to a time scale.

What is the general level of Linnaean System of Classification?

kingdom Level, organisms are single or multi celled whether they absorb, ingest or produce food.

which group do humans belong to?

Animalia

Plantae

Fungi

Protista

Monera

Humans are Animals

Metazoa is?

Animals are multicellular organisms composed of specialized cells

Members of the Kingdom Plantae are…?

mobile, they actively go out to get food and respond to stimuli

Phylum level of classification

grouped together, similarities in body structure or organization

phylum arthopoda

have external skeletons as well as jointed bodies and limbs

Which phylum do humans belong to?

Phylum Chordata

what is the basic plan all chordates share?

bilateral symmetry

left and right sides are mirror images of each other

chordates have gill slits used to obtain oxygen

What are Chordates divided into?

2 Subphyla

• Invertebrates

• vertebrates

vertebrates

• complex spinal cord late in development

• segmented vertebral (spinal) column of cartilage or bone

what is divided into seven living classes?

subphylum vertebrata

What exactly is a mammal?

endothermic

maintains constant body temperature

stable in core body

how to mammals conceive there young?

• the reproductive tract of the mother

• produce milk with their mammary glands

what are the 3 classes mammals can be divided into?

• prototherians

• metatherians

• eutherians

Prototherians

• lay eggs like non - mammalian vertebrates

• feed young with mammary glands

• only 3 rare surviving species

Metatheria

• marsupials characterized by birthing very immature young which will finish development in the mothers pouch.

Eutherians

• Mammal Species

• Placental Mammals

• mother carry their unborn offspring in uterus until development

• can be divided into 18 orders of mammals

humans belong order……

primata