Natural Selection Overview

Natural Selection Review

• ​Scientific Theory of Biological Evolution

• Modern organisms descended from a common ancestor over LONG periods of time.

Darwin's Contribution

• ​Darwin noted that species varied locally, globally, and over time.

• ​He drew ideas from other areas of study, to come up with his conclusions.

Galapagos Islands

Natural selection is a process in which organisms better suited to their environment are able to survive and reproduce more offspring

These favorable traits and characteristics are then passed on to their babies through a process called inheritance.

Multiple Choice

Why are advantageous traits more likely to be passed onto offspring?

• Because they are more likely to survive and reproduce.

• Because they come from dominant alleles.

• Because they come from recessive alleles.

• Because the organism knew it needed that trait, survives, and passes it on.

Multiple Choice

The differences among a species, like different bird beaks, are called

• genes.

• variations.

• traits.

• theories.

Multiple Choice

Where do adaptations come from?

• The individual organism decides to adapt

• Mutations that give an organism an advantage in its environment

• Genetic recombination during meiosis

• Both mutations and genetic recombination are sources of adaptation

Multiple Choice

Charles Darwin’s observation that finches of different species on the Galápagos Islands have many similar physical characteristics supports the hypothesis that these finches 
 

• have the ability to interbreed. have the ability to interbreed.

• acquired traits through use and disuse.

• all eat the same type of food.

• descended from a common ancestor.

Multiple Choice

Lamarck’s ideas about evolution include the concept that differences among the traits of organisms arise as a result of

• continual increases in population size.

• the actions of organisms as they use or fail to use body structures.

• an unchanging local environment.

• the natural variations already present within the population of organisms.

Multiple Choice

What did Darwin notice about the beaks of the finches?

• They were all the same

• The beaks seemed to match the food source.

• The beaks were not like any other bird beaks