Biology - Evolution Test Flashcards (Definitions Only)

Comparative Morphology (Definitions)

study of anatomical patterns. also the similarities and differences amongst the body plans of organisms.

Comparative Morphology (Properties)

• Only way to distinguish differences in species at that time

• Not most accurate way of determining relationships

George Cuvier (Belief)

thought unique geologic processes caused extinctions

Charles Lyell’s Belief

Theory of Uniformity - gradual, everyday geologic processes (e.g. erosion) shaped Earth over millions of years

Jean-Baptiste Lamarck’s Beliefs

• Traits were developed based on environmental needs

• Believed these acquired traits could be inherited

The Beagle

A Royal Navy ship that carried an important naturalist.

Charles Darwin

• Naturalist aboard the Beagle

• Made observations about geology, fossils, plants, and animals, known as the Voyage of the Beagle

Descent with modification

• traits change slightly from parents to offspring

Thomas Malthus (Significance)

Proposed the idea that famine, disease, and war limited the size of human populations.

Evolution by Natural Selection

• A theory applied by Charles Darwin broadly.

  • Individuals from every population struggled by competing for limited resources.

  • Some individuals have traits that make them better suited or ‘more fit‘ to their environment than others.

    • Increases fitness

Fitness

the ability to survive and reproduce

Adaptation

inherited trait that improves an individual’s ability to survive and reproduce

Natural Selection

process where environmental factors result in certain traits giving individuals in a population a higher probability of survival

Variations

differences among members of species, always provided by nature. some are favored by certain environments

Artificial selection

process where humans selectively breed organisms to produce the desired traits, sometimes regardless of fitness.

Alfred Wallace

Studied wildlife in the Amazon basin and arrived at the same hypothesis as Darwin. He was credited along with Darwin.

Factors vital to evolution are

genetic variation, overproduction, finite resources, natural selection

Genetic variation

Causes differences in organisms of the same species.

The original source of new alleles.

Mutations - errors in dna replication and environmental factors that favor a mutation

Crossing Over

Mixes up maternal and paternal alleles on homologous chromosomes for future gametes.

Independent Assortment

Apart of Meiosis 1, randomly distributing homologous chromosomes into gametes.

Fertilization

Combines alleles from two individuals.

Overproduction

More offspring are produced than will survive.

Finite Resources do what?

Drives competition among individuals in a population

Competition does what?

Drives natural selection

Selecting Agent

something that favors/selects for beneficial traits within a population

Natural selection and selecting agent

Conditions of the environment acts as this

Artificial selection and selecting agent

Humans act as this

Relative Age

Approximate Age

Absolute Age

Actual age of something

Where are fossils most found?

Inside of layers of sedimentary rock.

Where do younger fossils appear?

In higher rock layers above old layrs.

The fossil record will always be incomplete because:

Most ancient species had no hard parts to fossilize, or burial site had to escape destructive geological events

half-life

the time it takes for half of hte atoms in a sample of radioisotope to decay

Radioisotopes

Radioactive isotopes of certain elements, involved in radiometric dating.

Used to calculate how many half-lives passed since the organism died

14C to 12C

Alfred Wegener Belief

Theory of Plate Tectonics

Theory of Plate Tectonics Evidence

Fossils, geology, climate

Geologic time scale

Chronology of earth’s history that correlated geologic and evolutionary events

Homologous structure

Similar structure found in more than one species that may have different forms/functions; evidence of a common ancestor

Analogous Structure

similar in function/appearance but not in structure or origin; does not indicate a common ancestor

Morphological divergence

change from the body form of a common ancestor which produces homologous structures

Morphological Convergence

independent evolution of similar body parts in difference lineages, similar environmental conditions selected fro similar traits, produces analogous structures

Vestigial Structure

remnants of structures that were once functional in an ancestor; reduces in size, serve little to no function.

Similar genes give rise to;

similar proteins

Embryonic similarities show;

closer relation.

Homeotic Genes

Master genes that guide the formation of specific body parts during development.

Coevolution

Over time, two species depend on each other so much that they can no longer survive without each other/Two species evolve with each other.