4.6 - Adaptations

Question 1

T or F
All populations have some genetic diversity, or variables of genomes in individuals

Answer 1

True

Question 2

Why does genetic diversity exist?

Answer 2

• Random mutations while DNA is being copied create new traits
• Crossing over in parent chromosomes creates new combinations of genes (and therefore traits)

Question 3

What is adaptation?

Answer 3

a new trait that increases an organism’s fitness

Question 4

What is fitness?

Answer 4

the ability to survive and reproduce

Question 5

What is natural selection?

Answer 5

organisms that are better adapted to their env. survive and reproduce more offspring

Question 6

How does a whole population end up with an adaptation (how does evolution work?)

Answer 6

Individuals with adaptations pass them on to offspring & individuals without adaptations die off, which leads to the entire population having the adaptation over time (evolution)

Question 7

What is selective pressure/force?

Answer 7

the environmental condition that kills individuals without the adaptation

Question 8

What determines which adaptations an animal develops?

Answer 8

The environment

Question 9

What happens to traits as the environment changes?

Answer 9

• As environments change, different traits may become adaptations & old traits may become disadvantages
• a drought can kill off finches with smaller beaks, making larger beaks for cracking harder seeds an adaptation

Question 10

Explain pace of evolution

Answer 10

• The more rapidly an env. changes, the less likely a species in the env. will be to adapt to those changes
• If the pace of env. change is too rapid, many species may migrate out of the env. or die-off completely
• Ex: if the ocean warms too quickly, many species of fish may not be able to migrate before they run out of oxygen and suffocate

Question 11

Good genetic diversity leads to what?

Answer 11

The more genetic diversity in a population, the better they’re able to adapt to env. change (higher chance that some individuals have good mutations)

Question 12

What is the correlation between lifespan and pace of evolution?

Answer 12

• The longer the lifespan of the organism, the slower the rate of evolution
• bacteria & viruses can adapt and evolve in days vs humans evolution = thousands-mil. years