Lecture 6 P1

Question 1

What is the barebones definition of evolution?

Answer 1

change over time

Question 2

What is natural selection?

Answer 2

The struggle to survive and the natural variability among individuals results in some individuals being more likely to produce offspring. Is the mechanism for evolution.

Question 3

What is fitness?

Answer 3

The likelihood of that individual reaching sexual maturity and having offspring.

Question 4

Does evolution act on an individual or a population?

Answer 4

A population

Question 5

What is evolution by natural selection?

Answer 5

When species produce a descendant that looks very different from it’s ancestors because certain traits were more advantgeous in their environment so they had higher fitness and got selected for.

Question 6

Does natural selection act on the individual or the popln?

Answer 6

The individual

Question 7

The accumulation of small changes over time can cause what three things?

Answer 7

change within a species, form new species (if enough changes accumulate over time), or cause a species to go extinct

Question 8

A biological species is defined as what?

Answer 8

a group of individuals that actually or potentially interbreed in nature and produce fertile offspring

Question 9

What is linnaean taxonomy?

Answer 9

A classification system developed by Carolus Linnaeus

Question 10

What happened in the galapago islands, why did the small beaked birds die off? What kind of evolution does this cause?

Answer 10

Because the drought caused vegetation to stop producing seeds, the small seeds got consumed first, and so there was no food for small beaked birds and they died. This caused average beak size to increase.

Question 11

How does linnaean taxonomy work?

Answer 11

It ranks groups of organisms (taxa) into succesively smaller categories, large groups are identified by broad general features, smaller groups are defined by more specific unique features

Question 12

What is a slow example of evolution?

Answer 12

ceolacanth, the lineage has been around for a long time- the modern day one looks the same as the cretaceous one cause it’s deep water environment didnt change.

Question 13

is linnanean taxonomy based on evolution?

Answer 13

No it’s based on how similar organisms were to one another, the more features two organisms shared the more closely related they were assumed to be

Question 14

According to linnaean taxonomy are members within a taxon more closely related to each other than anything else?

Answer 14

yes

Question 15

Why are organisms with similar features likely related?

Answer 15

Because since genes influence physical appearance, then how an organism looks is related to it’s ancestory

Question 16

What are homologous structures?

Answer 16

Structures in animals that are similar to one another, for ex having four limbs, can be traced back to a single original structure in a common ancestor

Question 17

What is the linnaean taxonomy structure?

Answer 17

Kingdom phylum class order family genus species

Question 18

Why do pterosaurs, birds, bats, and humans all have the same bones in their forelimbs (humerus and alma)?

Answer 18

because they inherited these traits from a common ancestor

Question 19

What are analogous ancestors? Give an example?

Answer 19

features that look similar because they serve a similar function- not because they share similar ancestry.
for ex: the wings of a butterfly and a bat.

Question 20

What is convergent evolution?

Answer 20

is independent evolution of similar structures in groups who are not closely related

Question 21

What is a genetic anomaly?

Answer 21

When certain genes don’t get shut off and causes mutations to be present that shouldn’t.