BIO 191 CH 23

Adaptive radiation

Period of evolutionary change in which groups of organisms form many new species whose adaptations allow them to fill different ecological roles in their communities.

macroevolution

Evolutionary change above the species level. Examples of macroevolutionary change include the origin of a new group of organisms through a series of speciation events and the impact of mass extinction on the diversity of life and its subsequent recovery

mass extinction

The elimination of a large number of species throughout Earth, the result of global environmental changes.

pangaea

The supercontinent that formed near the end of the Paleozoic era, when plate movements brought all the landmasses of Earth together.

plate tectonics

The theory that the continents are part of great plates of Earth's crust that float on the hot, underlying portion of the mantle. Movements in the mantle cause the continents to move slowly over time.

radiometric dating

common technique used to determine the age of a fossil, based on the decay of radioactive isotopes

heterochrony

Evolutionary change in the timing or rate of an organism’s development

paedomorphosis

The retention in an adult organism of the juvenile features of its evolutionary ancestors.

homeotic genes

Any of the master regulatory genes that control placement and spatial organization of body parts in animals, plants, and fungi by controlling the developmental fate of groups of cells.

Understand the basics of radiometric dating and the importance of the fossil record.

based on radioactive isotopes can roughly estimate fossils up to 7500 years old, looking at half life

Explain how plate tectonics, mass extinction, and adaptive radiations have affected broad patterns of Earth’s life

These events create different habitates and niches which allow speciation to occur as groups are able to fill those niches and start to diverge

Describe the effects of developmental genes.

genes that control how an organism grows and develops, especially by regulating when, where, and how cells divide, differentiate, and form tissues and organs.

Explain the importance of homeotic genes.

developmental genes that determine the identity and placement of body parts during development. They are especially important because changes in these genes can cause one body structure to develop in the wrong location

Explain what it means to say that evolution is not goal oriented.

it’s a tinkering process, always changing and not linear

Explain how new forms can arise from changes in gene sequences and/or changes in gene regulation.

Its on the basis of gene favoring, the more favorable those genes are the increased production will occur