Biology 141N- Diversity of Life FINAL EXAM

inductive vs deductive reasoning

inductive- forms theories based on observations that may or may not be true (evolution)

deductive- tests theories with if…then… statements to be able to state facts “all normally developed humans have kidneys”

7 life properties

order

evolutionary adaptation

regulation

energy processing

growth and development

response to environment

reproduction

Strengths and limitations of science

strength- medicinal advancements, technological advancements, environmental solutions

weakness- uncertainty, questions we cannot study, science is always changing

focus of this course

core themes of biology

• evolutionary mechanisms

• resulting diversity of life

  • tree of life

crypsis

ability of animal to blend into environment

5 unifying themes of biology

organization

• molecules to biosphere

information

• genetic material

energy and matter

• transfer and transformation of energy

Interactions

• within organism (organ system)

• with environment and other organisms

evolution

• process of biological chance to adapt to differing environments over time

• descent with modification

Biological evolution

change in the heritable traits of biological populations over successive generations

population

all individuals living within the bounds of a certain area within their own ecosystem

adaptation

inherited characteristics of organisms that enhance their survival and reproduction in specific environments

Darwin

• descent with modification

• life evolves over time

• origin of species

• wanted classification (taxonomy) based on evolutionary relations

• studied strata fossils

• said if gradualism is true, earth is much older than thought

• naturalist

• voyage on the beagle

• galapagos islands

• adaptation of environment=origin of new species → finches and their beaks, tortoise and their shell patterns

• collected flora and fauna on islands

• collected fossils

• main conclusions

  • descent with modification → tree of life was born

  • adaptation by natural selection

• challenges traditional ways of viewing

Wallace

• developed similar theory to darwin

• father of biogeography

• collected birds, beetles, butterflies from amazon, but all was lost in wreck

• kept 8-year travel book from southeast asia adventures

• theory of evolution per natural selection was his thoughts

• pushed darwin to publish origin of species

Curvier

• geologist

• developed paleontology

• examined stratum in paris

• noticed young and old stratum

• noticed older strata = less similar fossils to modern species

• thought each new species development was catastrophic event

• did not believe in evolution

• influenced darwim

Hutton

• geologist

• earths geologic features could be explained by gradual mechanisms

• gradualism

• ex: valleys formed by river

• influenced darwin

Lyell

• geologist

• goes along with Hutton’s theory

• said the same geological processes are happening now as they were in the past at the same rate

• influenced darwin

Lamark

• proposed how life changes over time

• two theories

  • use and disuse → the correct part of this theory

    • use- get stronger

    • disuse- deteriorate

  • inheritance of acquired traits

    • organism passes modifications to offspring

    • is wrong because physical traits cannot be passed down

Endemic

long standing health condition within a population that is kind of steady-going

theory of evolution

process of descent with modification: characteristics present in an ancestral organism that altered by natural selection in its descendants over time as they are faced with different environmental conditions.

Convergent evolution

independent evolution of similar features in different lineages (sugar glider, flying squirrel)

maybe similar ecosystems, but in different locations

artificial selection

selective breeding with individuals that posses desired traits

homology

similarities in 2 organisms resulting from common ancestry

from common root

anatomical- bones or muscles

developmental- embryonic developmental stages

How does natural selection work?

individuals (offspring) who have certain inheritable traits survive and reproduce better (natural selection)

over time, natural selection can increase frequency of favorable adaptations in environment

in environment changes, process starts again

Three conditions

• over reproduction

• variation

• inheritable

Ex: black and white beetles

• black survive better because crypsis

• more black can reproduce so better black gene heredity

random genetic mutation

Convergent traits vs homologous traits

convergent- similar function and structure but did not develop from the same common ancestor

analogous traits- variations on a structural theme that was present in their common ancestor

why does evolution occur on a population level

an individuals genes do not change over a lifetime

happens to a group over generations of breeding with many switches in genetic makeup

Evidence discussed to support evolution by natural selection

• selective breeding is possible

• drug resistant bacteria like antibiotics

• homology and analogy

• fossil records

why natural selection cannot fashion perfect organisms

• random genetic mutation

• not goal oriented

• not always progressive trait mutations