| Terms |
Definitions |
|
Lyell?
|
|
|
Darwin’s Voyage
|
Draw Map
|
|
vestigial organs
|
pointless organs
|
|
Fitness
|
Measure of reproductive success
|
|
Geographic Distributionof Living Species
|
beaverNORTH AMERICAMuskratCapybaraSOUTH AMERICACoypuBeaverMuskratBeaver andMuskratCoypuCapybaraCoypu andCap
|
|
Mesozoic?
|
The Mesozoic (mez-uh-ZOH-ik) began about 245 million years ago and lasted about 180 million years. Some people call the Mesozoic the Age of Dinosaurs, yet dinosaurs were only one of many kinds of organisms that lived during this era. Mammals began to evolve during the Mesozoic.
|
|
Balancing Selection
|
Leads to balanced polymorphism (neither p or q are 1 or 0)
Heterozygote fitness: A1A2 is the most fit
q^ = q at equilibrium = s1/(s1+s2)
p^ = s2/(s1+s2)
Example: Sickle-cell heterozygosity
Frequency-dependent: Fitness varies with frequency of given genotypes
Example: Scale-eating fish; fitness varies with frequency of right vs. left-mouthed fish
|
|
Population Growth
|
Thomas Malthus: political economist, circa 1798–In “Essays on the Principles of Population,” he proposed the idea that if the human population continued to grow unchecked, sooner or later there would be insufficient living space and food for everyone.–Hence, there is a struggle for survival.
|
|
Darwin, Charles
|
Revolutionary scientist who proposed evolution by natural selection in his book "On the Origin of Species" published in 1859
|
|
selection
|
when organisms with more advantageous traits survive and reproduce while others do not
|
|
Species
|
A group of individuals that can interbreed to produce viable, fertile offspring (biological concept)
A group of individuals with a great number of morphological similarities (morphological concept)
|
|
Sympatric (Non-geographic) Speciation
|
Continued disruptive selection splits a species in two; also requires assortative (like x like) mating to minimize heterozygosity
Thought to be common among herbivorous insects
Ex: Apple Maggot Fly
Pre-1850s: Apple maggot fed only on Hawthorn Fruit (native to US)
Late 1800s: Apples added to diet; mating on host plant leads to reproductive isolation (Hawthorn and Apple fruits mature at different times)
|
|
Mutations and Natural Variation
|
Artificial Selection involves selective breeding of organisms that have natural variations or traits to produce organisms with desirable traits. •The variations needed for the origin of structural and physiological adaptations to occur are provided by mutations. •Mutations occur because of the introduction of new variations through mistakes in DNA replication.
|
|
Lamarck's Theory of Evolution
|
Jean-Baptiste Lamarck: French naturalist, circa 1809–He proposed that by selective use or disuse of organs, organisms acquired or lost certain traits during their lifetime. These traits could be passed on.
|
|
Direct Evidence for Evolution
|
Bacterial resistance•Coloring of moths changes in response to air pollution•Pesticide resistance•HIV resistance to drugs
|
|
Gould, Stephen Jay
|
Evolutionary biologist who proposed punctuated equilibrium in 1972
|
|
evolution
|
change of allele frequency in a population over time
|
|
What are microfossils?
|
Microscopic fossils of single-celled prokaryotic organisms that resemble modern bacteria have been found in rocks more than 3.5 billion years old Those first life forms must have evolved in the absence of oxygen, because Earth's first atmosphere contained very little of that highly reactive gas.
|
|
Selection coefficent (1-w)
|
Used to determine strength of selection (higher s = stronger selection)
|
|
Evolution by Natural Selection
|
Struggle for Existence: species regularly compete for food and living space•Fitness: the ability of an organism to survive and reproduce in a specific environment•Adaptation: the evolution of structural, internal, and behavioral features that help an organism better survive in an environment and increase its fitness.
|
|
Indirect Evidence for Evolution•DNA:
|
Provides genetic evidence of similarities between organisms–The study is called cladistics
|
|
Theory
|
A theory is an explanation or model based on observation, experimentation, and reasoning. It has been tested and confirmed as a general principle helping to explain and predict natural phenomena.
|
|
An Ancient Changing Earth
|
James Hutton: geologist, circa 1795–Looking at the layering of soils through deposition, uplift, and erosion, he proposed that the earth must be much more than a few thousand years old.•Charles Lyell: geologist, circa 1833–In “Principles of Geology” he used examples of earthquakes, volcanoes, and flooding, and proposed that the geology of the earth is changing slowly.–Darwin brought the first volume of this book on his journey.
|
|
punctuated equilibrium
|
Theory that species spend long periods of time without evolving between spurts of quick change
|
|
analogous structure
|
similar in appearance or function, but derived from different ancestral structures
|
|
embryology
|
the study of the early stages of development in an organism, especially the comparison of closely related species.
|
|
homologous structures
|
ie. aligator leg, bird wing, mammal leg, all very similar which proves relation
|
|
Cenozoic?
|
It began about 65 million years ago and continues to the present. The Cenozoic is sometimes called the Age of Mammals because mammals became common during this time.
|
|
Allopatric (Geographic) Speciation
|
A barrier to gene flow/migration (rise in sea level, mtn formation, etc) within a species' geographic range isolates subgroups. If the 2 new 'sub-ranges' are different enough, the two subspecies will undergo local adaptation and diverge from one another; loss of reproduction between subspecies heralds speciation
Post-zygotic isolation occurs first, pre-zygotic occurs later (reinforcement); interbreeding is impossible even if subspecies come back together
Special case: Founder effect
|
|
Relative fitness (w)
|
Each fitness divided by the highest fitness
Ex: fitnesses of 0.1,0.2,0.6
w = 0.16, 0.33, 1
|
|
Indirect Evidence for Evolution•Fossils
|
Provide a record of evolutionary intermediates
|
|
There is grandeur in this view of life, [that] from so simple a beginning, endless forms most beautiful and wonderful have been and are being evolved”,
|
Charles Darwin
|
|
radiometric dating
|
a method for dating rocks by measuring radioactive decay
|
|
Main aspect of Cenozoic?
|
During the Cenozoic, mammals evolved adaptations that allowed them to live in various environments—on land, in water, and even in the air
|
|
influences of Lamarck?
|
said that critters pass on acquired characteristics through selective use (false)
|
|
Darwin Presents His Case
|
In his 1858 presentation and 1859 publication of On the Origin of Species by Natural Selection Darwin tried to explain what he saw and proposed a theory of how species change over time. •In 1858, Alfred Wallace presents a paper speculating on evolution by natural selection. •Darwin and Wallace present their ideas together at the Linnaean Society on June 30, 1858
|
|
absolute dating
|
determining the exact age of a rock by means of radioactive dating
|
|
Main aspect of Mesozoic?
|
Events during the Mesozoic include the increasing dominance of dinosaurs. The Mesozoic is marked by the appearance of flowering plants.
|
|
What is endosymbiotic theory? Evidence?
|
The endosymbiotic theory proposes that eukaryotic cells arose from living communities formed by prokaryotic organisms. Lynn Margulis and her supporters built their argument on several pieces of evidence: First, mitochondria and chloroplasts contain DNA similar to bacterial DNA. Second, mitochondria and chloroplasts have ribosomes whose size and structure closely resemble those of bacteria. Third, like bacteria, mitochondria and chloroplasts reproduce by binary fission when the cells containing them divide by mitosis.
|
|
Indirect Evidence for EvolutionVestigial structures:
|
body structure that has no function in a present day organism but must have been adaptive to an ancestor–Example: tail bone in humans, blind mole rats, wings of flightless birds
|
|
What was in Earth's early atmosphere, and wat was the environment?
|
hydrogen cyanide, carbon dioxide, carbon monoxide, nitrogen, hydrogen sulfide, and water made up the atmosphere. 4 Billion yrs ago, earth cooled just enough to allow solid rocks to form. 3.8 Billion yrs ago, Earth's surface cooled enough that water could remain a liquid.
|
|
How did the oceans turn blue green?
|
Primitive oceans were brown bc they contained lots of dissolved iron. The earliest sedentary rocks, which were deposited in water, have been dated to this period ****LIFE APPEARED
|
