Chapter 1 test review

only triats that can be acted upon by natural selection are those controlled by

genes

The gradual change in species over time is called?

evolution

process by which individuals that are better adapted to the environment are more likely to produce

natural selection

Darwin noticed that birds had

different beaks based on the food they ate

what did darwin infer from his observations of orgamisms in south america and the galapagos island

small number of different plants and animals had come to the galapagos island for the mainland

rapid changes occur in species for short periods followed by long period of little or no chnage is called

puncuated equilibrium

a trait that helps an organism survive and reproduce is called

adaptation

through natural selection, what kind of variations gradually accumulate in a species

helpful

in the process or natural selection organisms best suited to their environment

are more likely to survive and reproduce

natural selection is affected by

variations

s species is a group of similar organisms that can

mate and reproduce fertile offspring

fossils, body structure, early development, DNA and protein source helps

determine evolutinary relationships.

Similarities in early development suggest that animals share a

common ancestor

when a species creates too many offspring than can possibly survive is

overproduction

How can a new species form?

When a group of individuals remains isolated from the rest of its species

when species are separated from another group and they live in a different environment it will change the species so much that it cant

reproduce

similar structures that are inherited from a common ancestor are known as

homologous structures

organisms on the galapagos islands had

changed over time

natural selection leads to evolution by

allowing animals with helpful variations will survive

differences in the same species are

variation

the more similar the DNA or species are

the closer related they are

forelimbs of birds and mammals are

homologous structures

A is a well tested concept that explains a wide range of observations

scientific theory

What are the four steps of natural selection? Give examples

1. Overproduction. This is species produce more offspring than can survive. An example is a sea turtle laying eggs and there not being enough resources for all of them.

2. Variation. This is when members of a species differ from each other in many of their traits. An example is the color, size, shape, and hardness of a turtle.

3. Competition. This is when resources are limited and species must compete with each other to survive. An example is some turtles may not find enough to eat. A slower turtle may be caught by a predator and a quicker turtle will survive and reproduce.

4. Selection. This is when individuals that are better adapted to their environment are more likely to survive and reproduce. An example is if a turtle is quicker than another turtle, the quick turtle will get the food first and will be able to survive and reproduce.

What happens when a species splits apart and isolated from each other in different environments and change to create different species?

When this occurs, the species will adapt to their new environment and they will one day be so different that they will be no longer able to mate and will become separate species.