Evidence of Evolution Notes

Evidence of Evolution

A scientific theory explains why something happens in nature and is supported by lots and lots of evidence.

​Read This! Review:
Theory of Evolution-Change over Time

Charles Darwin and many other scientists contributed to the development of this theory that explains how organisms change over generations to best thrive in the environment they live in.

​Read This! Review:
Theory of Evolution-Change over Time

Fossil Record

A fossil is any preserved remains, impression, or trace of an organism from the past.

How Fossils Supports Theory of Evolution

• Fossils provide a snapshot of the past

• Fossils can directly show how a species has changed over time

• Oldest fossils are on the bottom layers of the Earth's crust giving us an idea of what time period they lived.

Comparative Anatomy

Comparative Anatomy looks at similarities/differences within structures/parts of an organism
There are 3 main categories (to be discussed on next slides):
1. Vestigial Structures
2. Homologous Structures
3. Analogous Structures

Comparative Anatomy

Vestigial Structures:
Structures or features that many living organisms have, but no longer serve their original purpose due to evolutionary changes.


How it supports? They are "leftovers" from a past common ancestor. Used the hypothesize relationships among species.

Comparative Anatomy

Homologous Structures:
Features that are similar in structure but have different functions in different organisms


How it Supports? Scientists theorize that animals with similar structures likely evolved from a common ancestor

Comparative Anatomy

Analogous Structures:
A structure that perform a similar function but do NOT have a similar origin.


How it supports? These types of structures evolve differently and usually in response to best suit the environment the organism lives in.

Comparative Embryology

A branch if science that compares and contrasts embryos of different species and the patterns of their development.

An embryo is an early stage of development of an organisms

This line of evidence is "newer" because of recent technological advances

How Comparative Embryology Supports Theory of Evolution

• All vertebrate (organisms with a backbone) embryos develop in identical patterns to produce tissues and organs

• Similar patterns of embryological development provide evidence that organisms evolved from a common ancestor

Biogeography

Biogeography is the study of the distribution of organisms on Earth today and over time.

How Biogeography Supports Theory of Evolution

• Patterns of distribution of fossils (where the fossils are found) tell us how organisms evolved from ancestors

• Today, most species on the same continent are more closely related than organisms on different continents.

Molecular (DNA) Biology

DNA sequences can be used to determine how closely related organisms are to each other.

Molecular (DNA) Biology

Remember, all living things on Earth share the same universal code in DNA and RNA molecules

How Molecular Biology Support Theory of Evolution

• Species with similar DNA sequences share a more recent common ancestor and are more closely related

• This line of evidence is "newer" because of recent technological advances

Multiple Choice

Structures with the same parts have different functions; suggests that organisms share a common ancestry

• vestigial structures
• homologous structures
• adaptive radiation
• fossil

Multiple Choice

Study of embryos of various organisms to show a common ancestor because of similarities in development

• natural selection
• embryology
• speciation
• evolution

Multiple Choice

Two organisms that are closely related would have

• very similar DNA sequence
• exactly the same DNA sequences
• no proteins in common
• completely different DNA sequence

Multiple Choice

What does Darwin's theory of evolution suggest?

• species change over time
• extinct species are not related to living species
• different species can interbreed
• animals that look alike are most closely related

Multiple Choice

Structures are similar in appearance but not in structure

• Vestigial 
• Homologous 
• Analogous Structures 
• Embryonic 

Multiple Choice

The picture shows a/an ___________

• homologous structure

• vestigial structure

Multiple Choice

What is this an example of?

• Homologous structure

• Analogous structure

• Vestigial organs

• Functional adaption

Multiple Choice

Which of the following is an example of a vestigial structure?

• the wings of a red-tailed hawk
• the hind limbs of a house cat
• the fins of sharks
• the tailbone of a human

Multiple Choice

Which species’ DNA is most similar to the DNA of the toothed whale? 

• Hippopotamus 
• Baleen Whale
• Grazing Mammals
• Camels

Multiple Choice

What conclusions can be made based on this table shown?

• the American black bear and the giant panda are most closely related

• the giant panda and the red panda are most closely related

• the red panda and the racoon are the most closely related

• the giant panda and the racoon are most closely related

Multiple Choice

How do fossils provide evidence that evolution has happened on Earth?

• Fossils show how the sizes of certain animals has changed drastically over millions of years
• Fossils show that some species have gone extinct
• Fossils show how life forms present today are different than those from the past
• Different sedimentary rock layers provide evidence for how the environment has changed over time