Natural Selection and Evidence of Evolution

Where are older fossils found in the rock layer?

Older fossils are found deeper in the rock layer

How are fossil's age determined?

Radioactive dating is done to determine the approximate age of fossils

Fossils are then compared to newer animals to determine the evolution of the species. What is this called and the meaning?

Transitional forms, they are links between older and newer species

What is biogeography?

The study of the locations of organisms over a period of time

How are the same species of animals found in the different continents over time?

As continents were shifted the organisms were separated leading to their own evolution

What is the definition of comparative anatomy?

Comparison of internal and external structures of different species to see the results of evolution

Homologous Structure Definition?

Features of an organism that indicate a common ancestor

How can a species of animals from the same common ancestor be different from each other?

They inherited the same DNA from the common ancestor but they had few variations over time

What is one major difference between homologous and analogous structures?

Homologous Structures have the same structure but different functions whereas analogous structures have the same function but their DNA is different as they come from different common ancestors

Divergent Evolution Definition?

Species face challenges from the same environment, they may however branch off their evolution to survive

One characteristic of Divergent Evolution is?

New species share common ancestor so they have similar traits

Analogous Structures Definition?

Features of an organism, indicating they adapted to the same environment, but DOES NOT indicate a common ancestor

Convergent evolution Defintion?

Different species evolve with similar traits, however species are unrelated to each other

What is convergent evolution caused by?

Caused by living in the same environment meaning some challenges are caused

Vestigial Structure Definition?

Structures are remnants of an organism's past. They are no longer used, but indicates an ancestor once used them to survive

Embryology is the study of?

Embryo development in organisms

What is really similar in embryology to the development of vertebrates?

Both are really similar to each other, human and vertebrates

Why do we develop similarly?

Both inherited developmental instructions from a common ancestor, added new instructions to personalize the species

Biochemical Data is what?

Comparing DNA and amino acid sequences for the same gene/proteins and it is used to determine the % relatedness to each other

What exists in a population when looking at diversity?

Variation

Certain variations are ___

beneficial for survival

Organisims tend to overproduce, because of this not all of them survive what is caused because of this?

Due to overproduction and limited resources, competition exists, causing the population to change over time

Natural Selection?

the process of where organisms that are best suited to their environment will survive long enough to produce offspring, those not well suited will die

When environments present a challenge what is bound to happen?

Organisms with particular traits are better able to overcome these challenges, gradually able to reproduce and pass on their genes with this desirable trait, evolution will happen as well

What are some patterns of Natural Selection?

Organisms that are “fit” (have the desirable trait and reproduce) tend to survive the longest

Directional Pattern:

Traits are one extreme are favored, traits at the other extreme are against, overall shift in traits of population

Disruptive/Diversifying Pattern:

Both extremes are favored. “Average” trait is favored against

Stabilizing Pattern:

Selection against both extremes, “average traits” are selected for