What did Darwin conclude about the finches on the Galapagos Islands that later supported his theory of evolution? Check all that apply.
The finches on the Galapagos Islands all had the same beak.
The finches on the Galapagos Islands had different beaks.
The beaks of the finches stayed the same over time.
The beaks of the finches changed over time.
The Galapagos finches had a common ancestor.
The Galapagos finches did not have a common ancestor.
The finches on the Galapagos Islands had different beaks.
The beaks of the finches changed over time.
The Galapagos finches had a common ancestor.
Why do fossils support the theory of evolution? Check all that apply.
Fossils show that organisms descend from a common ancestor.
Fossils show that traits change slowly over time.
Fossils show that organisms inherit acquired characteristics.
Fossils show that evolution always occurs very rapidly.
Fossils show extinct species.
Fossils show that organisms descend from a common ancestor.
Fossils show that traits change slowly over time.
Fossils show extinct species.
Several kinds of bears are found on Earth. Most bears are brown or black, but one type of bear, the polar bear, is white. What process led to this difference in fur color? Explain your answer.
The difference in fur color between the polar bear and other types of bears can be attributed to the process of natural selection. Natural selection is a key mechanism of evolution proposed by Charles Darwin.
In the case of the bears, the variation in fur color was likely present within the ancestral population. Initially, there might have been a range of fur colors among the bears. Over time, certain variations provided a survival advantage in different environments.
In the case of polar bears, they inhabit Arctic regions where the environment is mostly covered in snow and ice. The white fur of polar bears acts as camouflage, helping them blend into the snowy surroundings and remain hidden from their prey. This advantageous adaptation increases their chances of a successful hunt, enabling them to better survive and reproduce.
On the other hand, brown or black bears are more common in forested or temperate regions where the dark coloration helps them camouflage in their habitat, such as among trees or rocks.
The difference in fur color arose through the process of natural selection, where specific traits that offer better survival and reproduction chances become more prevalent in a population over time. This process leads to the development of distinct adaptations that are well-suited to the specific environments in which these organisms live.
What are the four main components of Darwin’s theory of evolution?
The four main components of Darwin's theory of evolution are:
1. Variation: Individuals within a species exhibit variation in their traits. These variations can be physical attributes, behaviors, or genetic differences.
2. Inheritance: These variations are heritable and can be passed on from one generation to the next. Offspring inherit traits from their parents, contributing to the overall diversity within a population.
3. Selection: Some traits provide individuals with a survival advantage in their environment, allowing them to have higher reproductive success. These beneficial traits are more likely to be passed on to future generations.
4. Time: Evolution occurs gradually over long periods of time. Small changes accumulate over generations, leading to the development of new species from a common ancestor.