Map the mechanisms and concepts of EVOLUTION
por Teri L. Tucker
1. Humans (eg. plants (farmers) and animals (breeders)) determine traits desirable for reproduction, instead of nature. (Nicole Ethun)
2. "Survival of the fittest" - doesn't necessarily mean the strongest or biggest candidates, but those who possess the traits that will enable them to survive the best in their environment.
2.1. Survival of the fittest is always changing/evolving due to the ever-changing environment. Fitness is a direct correlation to the ability to adapt to the environment and produce new offspring. (Katie Wardsworth)
3. Population Bottleneck
3.1. when the majority of a population either cannot reproduce or is killed off.
3.1.1. This also could be caused by a loss of rare alleles in the blood that helps make this population bottleneck.
4. A group of organisms that can actually of potentially breed in nature
5. Human variation in skin color is a biological adaption. UV patterns across the globe play a role in the evolution of human skin pigment.(Andrew Wilkins)
6. can be difficult to apply this definition to certain organisms. For example bacteria reproduces asexually which directly contradicts the definition. Also plant and animals sometimes hybridize like the carrion and hooded crow. Should they be a separate species or the same?
7. Eukaryota
8. Developmental Adjustment is a change in natural human growth patterns that can be caused by cultural practices, such as foot binding. Also referred to as "Developmental Acclimatization", any changes that occur like this are mostly irreversible by adulthood.
8.1. is a process. Although strength is not a deterring adaptation in natural selection, it is not the main determining factor. It is not strength that determines who survive but rather the highest and most likely reproduction rates. (Kellee Bates)
9. Species
10. Charles Darwin
10.1. The first evolutionary scientist. Wrote a book, "The Origin of Species". The book explained Darwin's theory on scientific theory, evolution and natural selection. (
10.2. “It is not the strongest or the most intelligent who will survive but those who can best manage change.” ― Charles Darwin (Nicole Stevenson)
11. when a select few from a group or population goes off on their own to make a whole new population
11.1. This is known as migration , which is one of the four mechanisms of evolution. Geographic isolation may also play a roll in this as members of a population are separated, interbreed without interruptions, and create new gene pools different from the primary population.
12. For modifications to occur there must be variation within the population.
12.1. This is why natural selection is not a "perfecting" process. If it were, all individuals would be identical and evolution would eventually stop. Natural selection is arbitrary, favoring those with advantageous genes. However, diseases and dysmorphias still get passed down to offspring along with the successful genes.
13. Mutation and migration are two aspects influencing variation. (Katie Wardsworth)
14. Genetic Change can be influenced by many varying things such as mutation, environmental stress, and natural selection - Emma Matelich
14.1. Another interesting concept to go along with all these mechanisms of change is the idea of coevolution in which one species change effects another.
15. If you wanted to squeeze the 3.5 billion years of the history of life on Earth into a single minute, you would have to wait about 50 seconds for multicellular life to evolve, another four seconds for vertebrates to invade the land, and another four seconds for flowers to evolve — and only in the last 0.002 seconds would "modern" humans arise.
16. Migration can be a direct result of the necessity to survive for certain species. When an environment isnt healthy for a species to survive, they must relocate. After migration takes place, it can cause genetic evolution because of a need to develop certain traits. -Ayesha Horton
16.1. Another way evolution can occur given this specific scenario is had the species stayed, natural selection may have played a role to the point where in generations to come a population could be thriving in those harsh places.
17. Herbert Spencer coined this phrase "survival of the fittest" in describing the idea of natural selection. At the time this example of social darwinism referred to the degree of wealth, power and physical strength a person obtained and not the ability to reproduce from one generation to the next. (Andrew Wilkins)
17.1. "Survival of the fittest" does not always mean the strongest or the most powerful. It can be an arbitrary selection of advantageous genes to a certain environment.
18. common ancestor
18.1. After reading a fellow student's post last week, there is scientific theories that state that humans may have stemmed from the Neanderthal race. Other studies have uncovered several common traits between humans and the ape. I feel that most of this is a result of the level of intelligence from apes to humans. There are many theories of evolution in regards to our common ancestors, and these are just a few. - Ayesha Horton
18.2. Humans did not evolve from chimpanzees, though they are evolutionary cousins. They (we) share a recent common ancestor that was neither chimpanzee nor human. (Nicole Ethun)
19. descent with modification
19.1. This encompasses the idea that evolution is a means to a LONG TERM CHANGE.
20. Developmental Adjustment
20.1. Developmental Adjustment can also be caused by one's natural surroundings - children born at high altitudes in the mountains will naturally develop larger, more efficient lungs to cope with their surroundings.
21. Humans went through a change depending on where they lived.
21.1. Humans who live to higher elevations, have evolved to receive sufficient oxygen to survive. This is an example of micro-evolution, where genetic change occurs within a population. (Nicole Stevenson)
22. Cold places made melatonin white. these people are affected by skin cancer than the black skined people.
22.1. Pheomelanin, or red or yellow skin pigmentation, allows skin to better absorb vitamin D where less solar radiation is available
23. Hot humid places made skin (melatonin) dark.
23.1. Pheomelanin, or red or yellow skin, allows people to absorb vitaman D in areas thas there is little solar radiation available.
24. Pre-Darwain ideas of evolution
24.1. Ancient Greek idea of "evolution". Greek philosophers theory that all things came from water and air.
24.1.1. Aristotle's theory that there is always a transition period in living. All things evolve due to the desire to constantly be wanting to be divine.
24.2. Christian medical theory that creatures derived from a original divine form. Contrasts evolution.
24.3. Kant's descent theory involved based on organisms similarities that they may have come from just one ancestral source.
24.4. Change through use and disuse by Lamarck.
25. "Life not fixed." Evolution occurs over time, like a the neck neck of a giraffe growing longer over time to adapt to the height of trees. Organisms driven from simple to complex forms.
25.1. is a lineage-splitting event that produces a new form of species
25.2. Migration changes the breeding population of any organism. It can affect what traits are going to be more apt to survive in the new environment, and also can broaden the range an organism's population has. This in turn creates a larger breeding population that can again migrate. Migration can limit or enhance the chance for interbreeding, which changes the alleles that are inherit as a trait to the organism.
26. sex
26.1. Sex invariably leads to offspring. This could be nonrandom breeding, or interbreeding. Either way significant changes are made to the gene pool when this happens.
26.2. Sexual Selection
26.2.1. Special case of natural selection which depends upon organisms ability to successfully mate. often powerful enough to produce features that are harmful to individual survival. (Nicole Ethun)
27. Natural Selection
27.1. environment
27.2. The truth is natural selction...
27.2.1. is not random
27.2.2. it is mindless and mechanistic
27.2.3. it doesn't supply what an organism "needs"
27.3. Those who survive are the ones who can better adapt to their environments and therefor be able to produce more offspring through out the years.
28. Mutuation
28.1. Random mutations provide variations that help a species survive
28.1.1. Adaptation-an inherited characteristic that improves an organisms ability to survive and reproduce in a particular environment. (britaney clayton)
28.1.1.1. Humans and African apes may have shared a common ancestor. This common ancestor is unknown but is thought to have lived 5 to 8 million years ago.
28.1.1.2. Dominant, or more powerful, genetic traits have the tendency to influence the new generation of species. When looking at genetics within plants, more dominant species have the ability to invade a new environment, leading to “invasive” species. (Katie Wardsworth)
28.2. mutation creates variation, most unfavorable mutations not selected, reproduction and mutation occurs with faviorable variation and to survive and reproduce again.(Jennifer Hill)
28.3. Mutations can be caused by various factors. One cause stems from a DNA molecule copying imperfectly. Secondly, exposure to certain toxins can create a higher risk of genetic mutations to occur. - Ayesha Horton
28.4. The stresses inherent to a population's environment dictate the type of variations and adaptions which will be beneficial.
29. GENE FLOW
29.1. EXACHANGE OF GENES
29.1.1. Chromosomes & DNA: The Key to Inter-generational Evolutionary Development (Dan Kiesecker)
29.1.2. New node
29.1.2.1. New node
29.2. Definition
29.2.1. The transfer of genes from population to population. Commonly achieved by migration from one population to the next. (Isaac Wicks)
30. GENETIC DRIFT
30.1. FOUNDER'S EFFECT
30.1.1. Founder Effect is when the variation in a population lessens because new individuals are bred from a very small gene pool or population. (Isaac Wicks)
31. Descent
31.1. gene frequency
31.1.1. change within a population over time
31.1.1.1. heritable changes
31.1.1.2. Changes happen through diseases that spread overtime, by migration from and to a certain area, as well as the ability to survive in a certain environment.
32. Biological evolution, simply put, is descent with modification
33. Phylogenies
33.1. Methods used for dating evolutionary events
33.1.1. Radiometric dating
33.1.1.1. Uses half-life decay of radioactive elements to date rocks and minerals
33.1.2. Stratigraphy
33.1.2.1. Sequence of events from which relative dates can be determined
33.1.3. Molecular clocks
33.1.3.1. Amount of genetic divergence between organisms over time
33.2. A hypothesis that illustrates a pattern of relationships between species that represents modifications, splits, and divergent evolutionary paths of species. (Nicole Ethun)
33.2.1. Bacteria
33.2.1.1. New node
33.2.2. Archaea