Fossils Don’t Lie
What is a fossil?
Preserved remains or traces of organisms that lived in the past.
What are homologous structures?
Body parts with similar structures due to common ancestry.
What molecule carries genetic information in all living organisms?
DNA
What is biogeography?
The study of the geographic distribution of species.
What does “common ancestry” mean?
Different species evolved from a shared ancestor.
In what type of rock are fossils most commonly found?
Sedimentary rock.
Name one example of homologous structures in vertebrates.
Forelimbs of humans, bats, whales, or cats.
What does it mean if two species have very similar DNA sequences?
They are closely related.
On which islands did Darwin study finches?
The Galápagos Islands.
Name one line of evidence used to support evolution.
Fossils, DNA, homologous structures, embryology, or biogeography.
How does the order of fossils in rock layers provide evidence for evolution?
Older layers contain simpler organisms, while newer layers show more complex forms, showing change over time.
How do homologous structures support the idea of common ancestry?
They show that different species inherited similar traits from a shared ancestor.
Why is DNA evidence considered strong support for evolution?
DNA similarities show inherited traits from common ancestors.
How does biogeography support the theory of evolution?
Species are more closely related to nearby species than to those in similar environments far away.
Why is evolution supported by multiple lines of evidence instead of just one?
Multiple independent sources strengthen the scientific explanation.
Why are transitional fossils important evidence for evolution?
They show intermediate characteristics between ancestral and descendant species.
How are analogous structures different from homologous structures?
Analogous structures have similar functions but evolved independently, not from common ancestry.
How do protein similarities support the idea of common ancestry?
Similar proteins indicate shared genes passed down through evolution.
Why do island species often resemble mainland species?
They evolved from mainland ancestors that migrated and adapted.
How does embryology provide evidence for evolution?
Early embryos of different species show similar structures, indicating shared ancestry.
A fossil fish is found with both fins and limb-like bones. Explain how this supports common ancestry.
It shows a transition between aquatic and land organisms, indicating shared ancestry between fish and tetrapods.
Whales have small pelvic bones even though they don’t walk. Explain how this supports evolution.
The bones are vestigial structures inherited from land-dwelling ancestors, showing evolutionary change over time.
Humans and chimpanzees share about 98–99% of their DNA. What conclusion can scientists draw from this?
Humans and chimpanzees share a recent common ancestor.
Explain how continental drift helps explain similar fossils found on different continents.
Continents were once connected, allowing species to spread before drifting apart.
A student claims fossils alone are enough to prove evolution. Evaluate this claim using scientific reasoning.
Fossils are important, but combining fossils with genetic, anatomical, and geographic evidence provides stronger support.