Science - Chapter 8 Evolution
The process where populations accumulate inherited changes over time.
Define adaption and give specific examples.
A characteristic that helps an organism to survive and reprodue in their environment
An example are
What's the difference between fertile and sterile?
To be fertile an organism is able to produce fertile offspring
To be sterile an organism is unable to produce fertile offspring
What two conditions are necessary for fossil formation?
A fine layer of sediment must cover the carcass
Oxygen cannot touch the bones
How do fossils found in upper layers of soil differ from fossils foung in lower layers of soil?
Upper layered fossils look more similar to present day organisms
Lower layered fossils may be extinct
Why don't scientists have transition fossils for all plants and animals (gaps in the fossil record)?
Some fossils didn't meet the necessary conditions to be fossilized
Some might not have been found
How do transition fossils (such as those for the horse and whale) provide evidence for evolution?
The changes in bone structures as you get farther down in the soil show evolution. Layers that are closer to each other have more in common than layers that are far apart.
What is a vestigial structure?
A structure that was once usable
Give two examples of a vestigial structure from different organisms.
Human - tail bone, appendix
Whale - Hind limb
How do homologous structures (appendages of human, cat, dolphin, and bat) provide evidence for evolution?
They show how similar organisms evolved from a common ancestor. Homologous structures have different functions yet the same bone order.
What are two ways that DNA provides evidence for evolution?
Greater similarities between organisms means they have more in common
All organisms have DNA
How do embryos provide evidence for evolution?
They're similar at birth but as they grow up, they look different compared to one another.
What training did Darwin get in college?
He studied to be a minister (theology)
What was Darwin's job on the Beagle?
Naturalist - someone who studies plants and animals
Explain Darwin's thoughts in comparing finches he saw on the Galapagos Islands to those he saw in South America.
They looked very similar, but not identical
What is selective breeding?
Making deliberate crosses to produce offspring with wanted characteristics.
Give an example of selective breeding.
Mule - Donkey and Horse
How did selective breeding influence Darwin?
He thought the same could happen with animals in the wild but would take much longer.
What information did Charles Lyell provide about the Earth?
It's way older than what people thought (millions, not thousands)
How did Charles Lyell's information about the Earth influence Darwin?
He realized that animal polulations changed very slowly
What information did Thomas Malthus provide concerning populations?
Humans could reproduce beyond their food supply
How did Thomas Malthus' information concerning populations influence Darwin?
He figured out that animals can do the same (reproduce beyond their food supply)
How did Alfred Russell Wallace's ideas compare to Darwin's?
They were the same
What is Darwin's theory how evolution occurs?
What is responsible for the genetic variations we see in organisms?
What is the first step in Natural Selection? Describe it.
Overproduction - A species produces too much offspring
What is the second step in Natural Selection? Describe it.
Genetic Variation - Individuals of a species are slightly different based on inherited traits
What is the third step in Natural Selection? Describe it.
Struggle to Survive - The environment causes struggles for a species to survive
What is the fourth step in Natural Selection? Describe it.
Successful Reproduction - The more adapted organisms are more likely to survive than the less adapted
Explain an adaptation
Science - Chapter 8 Evolution
Science - Chapter 8 Evolution Review