Understanding Cladograms

Mr. Anderson explains cladograms, which are hypotheses about the relationships between organisms based on shared characteristics. He discusses how to create a cladogram, the importance of identifying outgroups, and the concept of common ancestors. The video also covers the theory of parsimony, which suggests the simplest explanation is often the most likely. Finally, Mr. Anderson highlights the use of DNA in modern cladogram construction to better understand evolutionary relationships.

What is the primary purpose of a cladogram?

• To provide a definitive evolutionary history

• To hypothesize relationships between organisms

• To determine the age of fossils

• To classify organisms based on size

In a cladogram, what is an outgroup?

• A group that is unrelated to the others

• A group that shares all characteristics

• A group with no shared characteristics

• A group with the most shared characteristics

How can you determine which species are more closely related in a cladogram?

• By comparing the size of the species

• By looking at the color of the branches

• By identifying the most recent common ancestor

• By counting the number of branches

What does a common ancestor in a cladogram represent?

• The oldest species in the diagram

• A species that shares characteristics with all descendants

• A species that is extinct

• A species that is unrelated to others

What does the theory of parsimony suggest in scientific hypotheses?

• The most complex explanation is usually correct

• The simplest explanation is often the best

• All explanations are equally valid

• The explanation with the most evidence is always right

Why might a species lose a characteristic in a cladogram?

• To become more colorful

• To increase its size

• Because of environmental changes

• Due to a lack of predators

What is a significant advantage of using DNA to create cladograms?

• It requires less expertise

• It is cheaper than other methods

• It provides more accurate evolutionary relationships

• It is faster than traditional methods

Which of the following is an example of a New World monkey?

• Orangutan

• Squirrel monkey

• Gibbon

• Baboon

How are physical characteristics used in traditional cladograms?

• To measure the size of organisms

• To identify unrelated species

• To classify organisms based on appearance

• To determine the age of species

What is the role of homology in DNA-based cladograms?

• To measure the size of DNA

• To find common ancestors through genetic similarities

• To determine the lifespan of species

• To identify unrelated species