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Physiological, anatomical, behavioral response to the environment. Adaptions result from evolutionary change.
Alternate forms of a gene. Occur at the same locus on paired chroms. and govern the same trait. Since they are different, their action may result in different expressions of that trait.
View that the Earth's landscape is from violent cataclysmic events. Cuvier's view counter to Lamarck's.
Describing a trait governed by an allele that's expressed in the presence of another allele. Prevent the expression of recessive alleles in heterozygous.
Position of a species within it's biological and physical environments. Diet, terrain, vegetation, type of predators, etc. unique to each given species.
Philosophy of race improvement through forced sterilization for one group and increased breeding for another.
Change in the genetic structure of a population. Used also for the appearance of a new species.
Segments of genes that are transcribed and are involved in protein synthesis. (ex denotes that they are expressed.)
Sequence of DNA bases that specifies the order of amino acids in an entire protein, a portion of a protein, or any functional product (RNA). Made up of hundreds or thousands of DNA bases organized into coding and non coding segments.
Evolutionary changes, or changes in allele frequencies, that are produced by random factors in small populations. Result of small population size.
Evolutionarily ancient family of regulatory genes that directs the development of the overall body plan and the segmentation of body tissues.
Nonrandom mating in which relatives mate more often than predicted under random mating conditions.
Segments of genes that are initially transcribed and then deleted. They arent expressed so they arent involved in protein synthesis.
Enzyme that breaks down lactose. Allows adults to ingest milk products. Discontinued production leads to lactose intolerance.
Postion or location of a chromosome where a given gene occurs. Sometimes used interchangeably with gene.
Cell division in specialized cells in ovaries and testes. Meiosis involves two divisions and results in four daughter cells, each containing only half the original number of chroms.. Can develop into gametes.
Structures contained within the cytoplasm of eukaryotic cells that convert energy, derived from nutrients, to a form that can be used by the cell.
Simple cell division; the process by which somatic cells divide to produce two identical daughter cells.
Refers to genetic change or changes in the frequencies of certain traits in populations due to differential reproductive success between individuals.
Basic units of the DNA molecule, composed of a sugar, a phosphate, and one of four DNA bases.
Referring to traits that are influenced by genes at 2 or more loci. Skin color, eye color, hair color.
Loci with more than one allele. Can be expressed in the phenotype as the result of gene action (as in ABO) or they can exist solely at the DNA level within noncoding regions.
Referring to species composed of populations that differ in the expression of one or more traits.
Member of the mammalian Primates. includes lemurs, lorises, tarsiers, monkeys, apes, and humans.
Study of the biology and behavior of nonhuman primates (lemurs, lorises, tarsiers, monkeys, apes).
3D molecule that serve a wide variety of functions through their ability to bind to other molecules.
Describing a trait that isnt expressed in heterozygous. Must be homozygous to be expressed.
Type of natural selection that operates on only one sex of a species. Results from competition for mates and can lead to sexual dimorphism regarding one or more traits.
Sickle Cell Anemia
Severe inherited hemoglobin disorder where red blood cells collapse when deprived of oxygen. Results from inherited 2 copies of a mutant allele. Type of mutation that produces sickle cell allele is a point mutation.
Theory that the Earth's features are the result of a long term processes that continue to operate in the present just as they did in the past. Elaborated on by Lyell, opposes catastrophism and contributed to the concept of immense geological time.
Narrowing of blood vessels to reduce blood flow to the skin. Involuntary response to cold and reduces heat loss on the skin's surface.
Expansion of blood vessels, permitting increased blood flow to the skin. Permits warming of the skin and facilitates radiation of warmth through cooling. involuntary.
Cell formed by the union of an egg cell and a sperm cell. Contains full completement of chroms.
Least amount of physiological change
Occurs in shortest period of time (sometimes immediately)
Reversible once individual returns to original environment
Example: hyperventilation at high altitude; "goosebumps"
Alfred Russel Wallace
Man who also has some of the same ideas as Darwin. Convinced Darwin to publish. (Natural Selection)
In colder climate's short appendages are adaptive because they are more effective at preventing heat loss. Longer appendages in warmer climates promote heat loss.
Relationship to body mass or volume to surface area. Body size is greater in pop. that live in colder areas. As mass increases, relative amount of surface area decreases proportionately. Increased mass allows for greater heat retention.
Nature "selects" those individuals whose traits better match the conditions of the environment
Individuals whose traits are a better match to the environment survive in greater numbers than those whose traits don't match as well
These favorable traits are passed on to offspring. Does not create new traits; traits must be inherited
Acts only on the variability that already exists in a population
Works only on traits that affect reproduction
Fitness is relative to the environment
If conditions of environment change beyond the abilities (existing traits) of population, it will become extinct
Extinction is the rule, NOT the exception
Opposed Lamarck's species change. Believed in fixity of species and came up with catastrophism.
Georges-Louis Leclerc de Buffon
Wrote Natural History. Recognized the external environment and living forms. Different regions have different pants and animals. Believed in a "center of origin" but not changes over time.
Dynamic relationship between species and the environment. External forces changed, then animal's pattern changed to accommodate. Result in increased or decreased use of certain body parts. "fluids and forces" would be directed to the parts that needed it. New trait would be passed on to offspring. Neck of giraffe stretches, neck becomes progressively longer, long necked descendents after many gens.
Great Chain of Being
Ranking extended to ethnic and racial groups
"Typical" abilities (character, morals, intelligence, temperament, etc.) fixed
Since organisms "breed true" (determined by heredity) no change is possible
"Natural" inferiority/superiority of people is part of Divine Plan
Strong supporter of empirical approach
Developed concept of "species"
Developed "binomial nomenclature"
still used in natural sciences today
Developed by the greeks and used in medicine. A way of diagnosing by bodily fluids in relation to temperament.
Paper inspired Darwin and Wallace. Wasn't interested in species change but of limiting population growth. Pops. increase when resources are plentiful/lack of predators. World would be a constant source of misery and famine of the pop. want kept in check.
Populations that reproduce sexually have the potential to grow at an exponential rate
Arithmetic vs. exponential growth
No population can continue to grow at exponential rate indefinitely
Growth stopped by limited food supply
"Surplus" offspring die
Coined the phrase survival of the fittest. Doesn't imply the toughest or meanest
In Darwin's terms refers simply to reproductive success
Fitness value of any trait depends on the environment--there are no absolutely fit traits
"Six Books of the Commonwealth"
"Method for Easy Comprehension of History"
Whites: predominance of phlegm
Asians: predominance of yellow bile
Africans: predominance of black bile
Indians: predominance of blood
As in original humoral theory, Bodin's scheme associates humoral-based races with characteristic temperaments:
Indians: (red skin/blood) are savage and warlike
Blacks: (black skin/black bile) are lethargic and slow-witted
Asians: (yellow skin/yellow bile) are cunning
Whites: (white skin/phlegm) are reflective and rational
is an ideology of society that seeks to apply biological concepts of Darwinism or of evolutionary theory to sociology and politics, often with the assumption that conflict between groups in society leads to social progress as superior groups outcompete inferior ones. Survival of the fittest bullshit.
Studied physical features (cephalic index) and culture of Sicilian immigrants
Followed up with same individuals 10 years later
Both culture and cephalic index had changed
Most notable changes between parents and children
Boas concluded that:
no relationship exists between race and culture
Even race changes with environment
Monk that lived in the Czech Republic. Worked with garden peas to investigate height and color.
Characteristics that are influenced by alleles at only one genetic locus. Ex. blood types ABO, sickle cell anemia.
Pop. gene pool needs to change in a specific direction. Some alleles need must consisitantly become more common while others become less common.
Science: the process of explaining natural phenomena
Hypothesis: provisional explanation requiring verification
Empirical: relying on experiment or observation
Data: facts from which conclusions can be drawn
Theory: a broad statement of scientific relationships or underlying principles that has been substantially verified through the testing of hypotheses; a tested explanation of facts
Why is sickle cell anemia important?
Best documented example of natural selection. It can kill people who have it, but selection favors it because it makes people resistant to malaria.
Define a particular body of theory
Describe the appropriate methods of study
Help define the questions/issues that the science addresses
Shortcomings of Natural Selection
Some traits may be selected for even though they actually make survival more difficult
Some examples: tail of peacock or large antlers on bull elk
Fitness value: reproductive success enhanced by these traits
Darwin called this "Sexual Selection"
Primary Influences on Darwin
Erasmus Darwin, his grandfather
Uniformitarian geology (Lyell)
Adaptation from Lamarck & others
Thomas Malthus and population dynamics
Immunity to different diseases
Presence/absence of certain enzyme
Hair color and texture
Shape of certain teet
Most dramatic of levels of response
Takes longest to develop
Develops only during growth and development of individual
Example: barrel chest at high altitudes
Focus still on ways of knowing God
Evolution of Evolution: Enlightenment (17th Century Europe)
Sexual reproduction increases genetic variation through random assortment of genetic material
Each parent can produce 8 million possible combinations; together 70 trillion! making a person's DNA specific to them
occurs when chromosomes don't separate during meiosis.
(ex. Trisomy 21/Down's Syndrome
is a union of ideas from several biological specialties which provides a widely accepted account of evolution. It is also referred to as the new synthesis, the modern synthesis, the evolutionary synthesis, millennium synthesis and the neo-Darwinian synthesis.
The synthesis, produced between 1936 and 1947, reflects the consensus about how evolution proceeds. The previous development of population genetics, between 1918 and 1932, was a stimulus, as it showed that Mendelian genetics was consistent with natural selection and gradual evolution. The synthesis is still, to a large extent, the current paradigm in evolutionary biology.
Hardy-Weinberg Equilibrium Theory
Compare the expected and observed genotype frequencies of a genetic trait controlled by a single locus (simple Mendelian trait) that has only 2 alleles. (A, a).
The frequency of the "A" allele is represented by "p".
The frequency of the "a" allele is represented by "q".
p + q = 1 (100% of all alleles for this trait in the gene pool)
To determine the expected frequencies of the possible genotypes, we compute the chances of alleles combining with one another in all possible combinations:
(p +q) (p + q) = p2 + 2pq + q2 = 1
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