Evolution Part 1

What is a Hypothesis? What is a theory?

a statement used to test an idea based on theory; an ideology that’s fundamental properties can help to make hypotheses

Micro vs Macroevolution

small changes overtime in a species that lead to macroevolution; large differences such as a new species being formed

Principles that favor natural selection in evolution are

genetic variation, variation is inheritable, survival is variable

What is the drug used to treat HIV?

AZT

What are two views for the istory of life?

Special creation - species do not change and Descent with Modification - species change overtime

Types of Naturalism

Methological Naturalism - scientific curiosity should use natural causes and processes to explain themselves, Ontological Naturalism - scientific claims should be only relevant to natural entities & processes, explicitly rejecting the existence of the supernatural

What makes a trait a vestigial trait?

Any trait that is less developed in a current species than its presumed ancestor, i.e, human tailbone and human appendix or stickleback fish with heavy or light armor

Species are separate once they are reproductively _______?

isolated

Stages of Speciation

1. Single variable population, 2. Distinguishable but interbreeding subpopulations 3. distinct populations with limited interbreeding, 4. reproductively siolated populations

Example of Speciation: Ring Species

is a connected series of neighbouring populations, each of which interbreeds with closely sited related populations, but for which there exist at least two end populations in the series which are too distantly related to interbreed, ex. greenish warbler

What does the term extirpation mean? What are fossils?

when a local population is wiped out; any record of previous physical life. They form in marshy or aquatic environments

Law of Succession

phenomenon where one speciies replaces another in the fossil reocrd and does the same thing

What are transitional forms in evolutionary studies?

They are extinct or extant organisms that display physical traits that are mixed b/w two organismal groups ex. Archaeopteryx: middlemen b/w dinosaurs and modern birds

Structural Homologies

structures in organisms that show they come from a common ancestory. i.e,. forelimsbs in mammals. bats, horses, whales etc

Analogy

a similarity of function due to convergent evoluation ex. dolphins and sharks having streamlined bodies

Transposons aka pseudogenes

genes that can jump from one chromosome to another ((are essentially erros in genetic code). They c

Artificial Seleciton in Evolutionary studies

when humans are controlling what genes get expressed in the next generation ie., cows that produce more meat etc

Natural Selection

Unlike artificial selection, it is typically based on the idea of “survival of the fittest” in that the most advantageous genes tend to move into the normal gene pool

Darwin’s Theory of Evolution By Natural Selection

When variation among individuals in a species is observed and inherited, more individuals are born that will survive to reproduce, and some variants survive and reproduce at higher rates than others

The Medium Ground Finch, Geospiza fortis

Beak size was seen to show that having a more mesenchymal Bmp4 gene tensds to correlate w/ beak depth and that environmental pressures influences beak size

Altruism in species is what?

when a species does an act for the benefit of another of their species.

According to Darwin, if a species became for homophenotypic, then

 which will cause the species diversity to decrease, causing the species to have less evolutionary fitness 

Synthesis of Darwin