AP Biology Chapter 22
Terms in this set (39)
On the Origin of Species
Darwin; many modern species are decendents of ancestral species; the mechanism for this evolutionary process is natural selection
A population can change over generations if individuals with certain heritable traits leave more offspring than others. Result=evolutionary adaptation.
the accumulation of inherited characteristics that enhance an organisms ability to survive and reproduce in a specific enviroment.
change over time in the genectic composition of a population, also refers to the gradual appearance of all biological diversity
All Living forms could be arranged on a scale, ladder of increasing complexity, later called the "scale of nature" Opposed any concept of evolution and viewed species as fixed and unchanging.
Species were individually designed by God and perfect
Swedish Physician and Botanist, founded taxonomy. Grouped similiar species into increasingly general catergories. Similarity between species did not imply evolution but pattern of creation.
Linnaeus, a system for naming species and classifying species into a heirarchy of increasingly complex organisms. Kingdom, Phylum, Class, Order, Family, Genus, Species
Linnaeus, naming organisms according to genus and species
Darwin's Influence by?
Fossils, Remains, Traces of Organisms from Sedimentary Rocks
developed Paleontology; study of fossils. Documented in Paris Basin---> documented succession of fossil species and found extinction to be common.
Who adopted Catastrophism?
Cuvier------------> speculation that boundaries between strata were due to local floods or droughts that destroyed species. Eventually repopulated by species immigrating from unaffected areas.
Geology= Theory of Gradualism----> Geological changes took place slowly but its a continous process.
Theory of Uniformiarinism, geological processes had not changed throughout Earth's history.
Who had influence on Darwin
Hutton and Lyell= Geologic Events are slow than Earth must be older than 6,000 yrs old estimated from Bible. Second, Gradualism can produce substantial change over long period of time.
Jean Baptiste Lamarck
Applied Concept of Gradualism to Biological Evolution Proposed two mechanisms for Evolution..Use and Disuse, Inheritance of Acquired Characteristics. Thought that evolutionary change was driven by innate drive of organisms to increasing complexity.
"Use and Disuse"
Lamarck---------->Parts of the body that are used become larger and stronger whereas parts that are not used dissappear.
Inheritance of Acquired Characteristics
Modifications acquired during ones lifetime can be passed to offspring. BIGGEST Mistake to contribution of Evolution. Larmarck
Alfred Russel Wallace
Young Naturalist also developed Natural Selection Theory
Descent with Modifcation
All organisms are related through descent from a common ancestor that lived in the remote past. Over evolutionary time, the descendants of that common ancestor develop modifications or adaptations that allow them to reproduce in specific habitats.
dissected logic of Darwins Theory into three inferences based on five observations
Population size would increase---> organisms reproduced successfully
Populations tend to remain stable in size except for seasonal fluctuations.
Enviromental Resources are limited. Inference #1---Production of more individuals than enviroment can lead to struggle for existence with only fraction of offspring surviving.
Individuals of a population vary extensively in their characteristics. No two individuals are alike.
Much of this variation is heritable. Inference #2---Survival in the struggle for existence is not random but depends on inherited traits. Inference #3----This unequal ability of individuals to survive and reproduce will lead to a gradual change in population with favorable characteristics accumulating.
influenced Darwin.."overproduction" Human Suffering--disease, famine, was the inescapable consequence of the potential for human populations to increase faster than food supplies and other resources.
Differential Reproductive Success
Organisms with traits favored by the enviroment produce more offspring than do organisms without those traits--results in the favored traits being disproportionately represented in the next generation.
modifying a variety of domesticated plants and animals over many generations by selecting individuals with the desired traits as breeding stock.
Darwins Main Idea 1
Natural Selection is differential success in reproduction (unequal ability of individuals to survive and reproduce) results from individuals that vary in heritable traits and their enviroment.
Darwins Main Idea 2
The Product of Natural Selection is the Increasing adaptation of organisms to their enviroment.
Darwins Main Idea 3
If an enviroment changes over time, or if individuals of a species move to a new enviroment, Natural Selection may result in adaptation to the new conditions, sometimes giving rise to a new species in the process.
Evolution Through Natural Selection
Individuals do not Evolve---Natural Selection can act only on heritable traits, traits that are passed from organisms to their offspring (editing mechanism) it cannot create favorable traits It can only act on existing variation----A trait that is favorable in one enviroment may be useless or detrimental in another.
John Endler & David Reznick
Similarity in characteristic traits from common ancestry. Forelimbs in humans, cats, whales. All have different functions. Not obvious in adults but evident at embryonic development. Anatomical Similarites, Vestigial Organs, Genes and Protein, Genetic Code.
No importance to organism, but had important functions in ancestors. Some are homologous structures.
Similiar Function but did not arise the same..wings in insects, wings in bird, wings in bat.
Species tend to be more closely related to other species from same area than to other species with the same way of life that live in different areas.
Succession of Life Forms is consistent with Descent of Modification