bio lecture 1 + readings

why is evolution important?

- unifying concept in bio

- affects other areas (medicine, agriculture, conservation)

- creates diversity

who is Jean-Baptiste de Lamarck (1744-1829)

- First to use the term evolution and think that animals can change during their lifetime EX: giraffes and long necks

- First to create a hypothesis for how animals inherit traits from parents to adapt

who is Charles Lyell (1797-1875)

- said the world is changing all the time and can be examined through slow processes over time

- (erosion, earthquakes, volcanoes, etc.) can

explain the history of the Earth

what were the insights that Charles Darwin and Alfred Russell Wallace come up with

- Evolution occurs (descent with modification)

- Natural selection is a mechanism for evolution

• The concept of common descent explains how all species share a common ancestor.

evolution

change in a population's inherited traits over generations

natural selection... what does it lead to?

process where orgs with a more advantageous trait survive and have more babies than those without

- advantageous traits become common over time

- leads to adaptation

for natural selection to occur, it needs:

1. variation in a pop

2. variation needs to be heritable

3. fitness: some orgs are more successful at survival and reproduction

biodiversity

all life on earth/the kinds of living orgs in an area

adaptation

a trait that makes an org better able to survive and reproduce/the verb; process

what's the basic structure of Biological Evolution?

- Populations are made up of individuals that differ and must be heritable for evolution to occur

- From generation to generation, these attributes can change in frequency in a population

macroevolution vs microevolution?

Microevolution: evolution within species

Macroevolution: evolution among species

WHY and HOW is evolution studied?

WHY:

- Determine the processes responsible for evolutionary change (e.g.,

natural selection)

- Identify the major forces of evolution

HOW:

- Make observations, recognize patterns

- Theoretical: develop models (turning thinking into hypotheses that can be tested)

- Comparative: obtain data from many species to understand if the things observed can be applied generally

- Experimental: do experiments to address a hypothesis

why in some cases does evolution NOT equal natural selection

- Evolution does not have to be caused by natural selection (mutation, genetic drift, migration)

- Natural selection does not always cause evolution (only if the trait is heritable. Ex. Muscle mass is advantageous but not inherited)

what is a phylogenetic tree?

shows the relationships between species