Natural Selection

#5 - Whether or not a trait is adaptive depends on the _____________________.

Environment

#7a - _________________ are instructions for making protein molecules and ____________________ determine an organism's traits.

Genes, protein molecules

Biologists study a population of lobsters and discover a mutation for exoskeleton color causing some lobsters to be blue. They discover that blue lobsters live just as long as the typical dark green lobster. Is this mutation an adaptive or non-adaptive trait?

It is neither an adaptive or non-adaptive trait because it doesn't help the lobsters or hurt them.

#9b - _______________ to genes can sometimes introduce new traits into a population.

Mutations

#7b - Individuals inherit their genes from their ____________. Genes, and therefor traits, in a population are passed down from _____________________ to _______________.

Parents, generation, generation

In class we studied two different populations of ostrilopes. We discussed how the populations changed when the environment got cold. In one population, the ostrilopes distribution changed to have more individuals with thick fur. In the other population, the ostrilopes went extinct. What would cause one ostrilope population to change and the other to all die?

The ostrilope population that changed had more variation in their traits and thick fur became an adaptive trait. Those ostrilopes lived and passed on their traits to further generations. The other ostrilope population had less variation in their traits and had no ostrilopes with thick fur to survive and pass on their traits.

A redbird population that lives in a forest has variation in beak size. Some birds have thicker beaks and can easily open and eat seeds with hard shells. Some birds have thinner beaks and can easily reach and eat the seeds inside pinecones. What would be an adaptive beak trait if most of the available food in the forest is in pinecones?

Thinner beak

A population of foxes' fur color trait distribution changes over time from a few white and mostly dark grey to mostly white and some some dark grey. What was the cause of this effect on trait distribution?

a change in the environment to make white fur color the adaptive trait

Define generation

a group of individuals born and living at about the same time

Define population

a group of the same type of organism living in the same area

A population of seals' environment changes from warm where thin blubber was the adaptive trait to cold where thick blubber becomes the adaptive trait. However, the starting population had no seals with thick blubber. Where did the seals with thick blubber come from?

a mutation in the seals' genes

Define mutation

a random change to a gene that sometimes results in a new trait

Define trait

a specific characteristic of an individual organism

Define non-adaptive trait

a trait that makes it less likely that an individual will survive in a specific environment

Define adaptive trait

a trait that makes it more likely that na individual will survive in a specific environment

Define protein molecule

a type of large molecule that performs important functions inside organisms

#10 - A new trait will only become more common in a population if it is _____________________.

adaptive

#3 - Over many generations, individuals with _________________ traits become more common in a population, while individuals with ______________________ traits become lesson common.

adaptive, non-adaptive

Define prediction

an idea about what might happen that is based on what you already know

Define gene

an instruction for making a protein molecule

Define variation

any difference in traits between individual organisms

#2 - The number of individuals with each trait in a population can ..........

change over time.

Define environment

everything (living and non-living) that surrounds an organism

#9a - Mutations are changes to ______________ that can lead to changes to protein molecules, which can result in changes to _________________.

genes, traits

#8 - Individuals with adaptive traits are more likely to ___________________________ and have ________________; individuals with non-adaptive traits are more likely to die without having offspring.

live longer, offspring

#1 - A __________________ can be described by the traits present and by the number of individuals who have each trait.

population

#6 - Biologists analyze data about environmental conditions (_________________) to explain changes in the distribution of traits in populations (_________________).

the causes, the effects

Define distribution

the number of individuals with each trait in a population

Define natural selection

the process by which the distribution of traits in a population changes over many generations

#4 - The ____________ that exist in a population determine which traits can become more common over many generations.

traits