Unit 8 flashcard 1 H

Front

What did Charles Darwin and most contemporary scientists believe about species when he set sail on the HMS Beagle?

Back

Each species was specially created by God in its present form and did not change over time.

Front

What type of selection is described when medium-sized lizards survive while small and large lizards do not?

Back

Stabilizing selection.

Front

Why did the number of white peppered moths decrease by 1895?

Back

They did not blend in with the trees and birds ate them.

Front

What was one of Alfred Russel Wallace's major motivations for his travels besides selling specimens?

Back

To understand the origin of species.

Front

What are the hind leg bones in a whale an example of?

Back

Vestigial structures.

Front

Define 'natural selection'.

Back

The process by which organisms better adapted to their environment tend to survive and produce more offspring.

Front

What is a homologous structure?

Back

An anatomical feature in different species that is similar due to shared ancestry.

Front

What is the difference between homologous and analogous structures?

Back

Homologous structures arise from a common ancestor, while analogous structures arise independently in different species due to similar environmental pressures.

Front

What is the significance of vestigial structures in evolution?

Back

They provide evidence of an organism's evolutionary past and show how species have changed over time.

Front

What is directional selection?

Back

A type of natural selection that favors one extreme phenotype over the mean or other extreme phenotypes.