Chapter 5.1 Evolution

gene

a sequence of DNA that codes for a particular trait

adaptation

a heritable trait that increases an individual's fitness

fitness

how reproductively successful an organism is in its environment.

artificial selection

breeding animals or plants with trait humans want to see expressed. We pick the trait instead of letting nature "select" what traits are best suited for a given environment.

2 common examples of artificial selection

Dog breeding and agriculture

speciation

process by which new species are generated over thousands of generations.

extinction

the disappearance of a species from Earth, and will occur when environmental conditions change rapidly or severely enough that a species cannot adapt to the change.

gene flow

Movement of genes into or out of a population due to the migration of individuals to or from the population

natural selection

process by which traits that improve an organism's chances for survival and reproduction are passed on more frequently to future generation. The environmental conditions will choose the more favorable trait.

Mass extinction

A catastrophic, widespread, often global event in which major groups of species are wiped out over a short time compared with normal (background) extinctions.

List the four primary mechanisms of biological evolution

1.) Mutation
2.) Migration
3.) Genetic drift
4.) Natural Selection

What does the phrase "survival of the fitness" mean?

an individual with high fitness produces more offspring and therefore passes on its genes more frequently than an individual with low fitness.

What is the connection between adaptations and fitness?

Adaptations increase an organism's fitness in its current environment

What term is used to describe how reproductively successful an organism is in its environment?

Fitness

What term describes changes in DNA that can be good or bad for an organism?

mutations

A change in a population's gene pool over time is considered to be an example of...

biological evolution

A ________ is a sequence of DNA that codes for a particular trait, (Ex. brown hair, blue eyes).

gene

What term do Biologist refer to when they discuss a "Change over Time"?

Evolution

Gene flow in and out of a population can cause change in the gene pool do to ...

Migration, Emigration and Immigration

The sharp teeth a shark inherits from its parents and uses to feed are an example of a(n)...

adaptation

A population of deer is separated by chance (hunting, river formation), this could cause...

Genetic Drift

If the following are present in a new environment, a species is unlikely to become invasive...

predators, parasites, and competitors

Why might the zebra and quagga mussel invasion have happened so quickly?

They have a high biotic potential, are strong competitors, and have a high carrying capacity.

A trait must be ___________ in order to be passed from parent to offspring.

heritable

gene pool

a collection of different genes.

What are the 3 conditions of natural selection?

1.) organisms produce more offspring than can survive
2.) individuals of a species vary in their characteristics.
3.) Individuals vary in their fitness or reproductive success.

acquired traits

physical characteristics or behavior of an organism not inherited or genetically passed down

evolution

A change in a population's gene pool over a long period of time.

biological evolution can occur 4 ways

mutations, migration, genetic drift, natural selection

mutation

accidental changes in DNA that can cause variation among individuals and can be passed onto offspring.

migration

immigration (into) or emigration (out) of a population could cause a change in the proportion of a gene.

genetic drift

an unusual event causes a few individual to be separates from the whole population, causing the next generation to have a different gene pool from the original population.

invasive species

plants and animals that have migrated to places where they are not native

allopatric speciation

The formation of new species in populations that are geographically isolated from one another.

Allopatric

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