lecture 2

Question 1

List and describe the two explanations of biological phenomenon

Answer 1

1. Proximate causes are the immediate physiological reasons for a certain phenomenon like hormones, structures
2. Ultimate causes are the overall causes of evolution like the history of birds ancestors singing, it lies in history of events that led to the evolution of birds singing

Question 2

List the common misconceptions of evolution discussed on class. Explain three of these misconceptions in more detail

Answer 2

Misconceptions: Natural selection is evolution, we evolved from apes, organisms evolve adaptations they need, evolution is random, evolution is simple to complex, evolution promotes selfishness and cruelty, evolution is just a theory.
1. Evolution is not just a theory because there are multiple lines of evidence backing it to explain it and is widely accepted by almost all scientists.
2. We did not evolve from apes, but we do share a common ancestor that we diverged from.
3. Natural selection is not evolution, but natural selection is one of the mechanisms that drives evolution like genetic drift and sexual selection.

Question 3

3 Ideas leading to modern evolutionary thought

Answer 3

1. Darwin’s theory of** natural selection** where based on specific traits that are well suited for an environment will be selected for more in breeding because those with an adaptation better suited for the environment will survive to breed.
2. Mendel with the inheritance of traits, he discovered the mechanism for which genes are passed on to offspring and therefore providing the genetic pathway for evolution.
3. Motoo Kimura with the Neutral theory, which is where DNA sequences evolve by chance like in genetic drift rather than natural selection, but we know that random genetic mutations occur like Kimura says but they work in tandem with natural selection to drive evolution

Question 4

What are the two major theories in Darwin’s “The origins of Species” ?

Answer 4

1. Natural selection
2. Descent with modification

Question 5

What are the 5 distinct components of Darwin’s theory of evolution?

Answer 5

1. Evolution
2. Common descent
3. Gradualism: descent with modification
4. Population change:
5. Natural selection

Question 6

What is the modern synthesis? Be sure to specify the two major components of the modern synthesis in your answer.

Answer 6

Main principle was adaptive evolution is caused by natural selection acting on genetic variation.
Mathematical theory of population genetics, showed that mutation and natural selection together cause adaptive evolution
Mutations are the driver or raw material for natural selection

Question 7

Name one other major theory to that emerged in the Post-Darwinian era.

Answer 7

Gregor Mendel gene inheritance and Kimura’s neutral theory where genetic drift is also a driver of natural selection and the concept of molecular evolution.

Question 8

Science is a process of acquiring an understanding of natural phenomenon. What are two components of this process?

Answer 8

One component of this process is posing a hypothesis which must be testable.
The second component is testing them with observational or experimental evidence which is where scientists must be able to quantify or qualify a process by performing an experiment of by observation that proves their hypothesis or renders it null.

Question 9

What are two important aspects of character evolution that the fossil record documents?

Answer 9

Mosaic evolution is shown through the fossil record because individual features are show up at different times in the fossil record confirming that the features developed independently of each other.
Gradual change in individual features is shown in the records because they can see a specific feature change overtime and transition into a new one like from a fin for swimming to a limb for walking

Question 10

List four lines (or types) of evidence for evolution?

Answer 10

Mosaic evolution is shown through the fossil record because individual features are show up at different times in the fossil record confirming that the features developed independently of each other.
Gradual change in individual features is shown in the records because they can see a specific feature change overtime and transition into a new one like from a fin for swimming to a limb for walking
Molecular phylogenetic trees support the morphological trees with commonality between genetics of different species and shows where they split.
Molecular biology and genomics show the commonality of all living things because we share some very similar features in the genome.
Biogeography is one because this shows that different animal taxa correspond to the different geographical locations due to the fact that animals evolve based on their specific environments.

Question 11

What are the two major processes of long-term evolution? Describe one difference between these processes.

Answer 11

Anagenesis: rare, speciation without splitting
Cladogenesis: common, ancestor split into 2+ descendent species

Question 12

What are three practical applications of evolutionary science?

Answer 12

Biomimetics: where parts of animals are looked at to create helpful technology
Conservation
Agriculture

Question 13

Describe two examples of the connection between evolution and the onset of human disease.

Answer 13

Mismatch with modern environment can happen because our modern environment is changing faster than we can evolve so that results in new diseases like obesity and type 2 diabetes because people are eating way more than we used to due to agriculture and industrial revolution.
Many Genetic diseases are due to mutation in the genome that are beneficial earlier in life but are detrimental later in life (post period of reproduction) because humans are living longer than we used to so the mutations that helped us earlier in life and didn’t show up in past generations is because past generations didn’t live long enough to experience them.