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Speciation

The process of one species becoming two species over time

Transitional Forms

1) Can be found in fossil record, but the lack of transitional forms in fossil record Darwin attributed to the rarity of fossilization. 2) Transitional forms might be present in living organisms so that living intermediates are not seen because they conti

Absolute Dating

determine actual age of fossil, compare amount of radioactive element in sample to amount of element into which it breaks down

Relative Dating

method of determining the age of a fossil by comparing its placement with that of fossils in other layers of rock

Sedimentary Rock

The layer in which most fossils are found

Punctuated Equilibrium

Where species appear to exist in the same form for long periods of time, but then some disaster wipes out millions of species all at once and new species rapidly evolve to fill newly empty niches.

Homologous Structures

Structures that look physically similar because they come from a common ancestor, even though they may have different functions now.

Divergent Evolution

An ancestral organism diverged to exploit two or more different ecological niches

Analogous Structures

Look physically similar because they share a common function, but the structures did not come from a common ancestor

Convergent Evolution

when two or more species NOT descended from a common ancestor develop similar traits

Vestigial Structures

remnant of a structure that may have had an important function in a species' ancestors, but has no clear function in the modern species.

Permineralization

The process by which minerals replace parts of an organism.

Carbonization

Process in which plant materials are changed into carbon. Often preserves the parts of plants.

Trace Fossils

fossils that provide evidence of the activities of ancient organisms such as footprints or animal droppings

Observations

A personal experience as seen through one of the senses, influenced by background knowledge and personal experiences

Bloom's Taxonomy

(base to top) Knowledge, Comprehension, Application, Analysis, Synthesis, Evaluation

Hypothesis

An educated guess that can be falsified

Falsifiability

the degree to which a scientific theory makes unambiguous predictions that can be tested against the facts

Predictions

Not a single statement but two statements connected with the conditional IF and THEN

Results

Plainly observable things that no one can disagree with

Conclusions

Is an interpretation of the results, and can always be disputed

Variables

the different factors that can change in an experiment

Independent Variable

The experimental factor that is manipulated; the variable whose effect is being studied.

Dependent Variable

the outcome factor; the variable that may change in response to manipulations of the independent variable.

Controlled Variables

Variables in an experiment that are kept the same throughout the experiment.

Theory

is much more than a guess, it is often as close to proof as a scientific idea can get.

Law

Describes the behavior of physical properties we humans define based on our observations

All living things...

Metabolize, sense and respond to the environment, grow and reproduce

Metabolism

set of chemical reactions through which an organism builds up or breaks down materials as it carries out its life processes

Homeostasis

the ability of a living thing to keep conditions inside its body constant

Taxonomy

The classification of living things into categories