Chapter 21 - Phylogeny, Speciation, and Extinction

Murchison meteorite

The \________ (discovered in Australia in 1969) included sugars and over 70 distinct amino acids, lending support to this notion.

Inorganic materials

\________ found in Earth's early atmosphere reacted to form the building blocks of living molecules.

distinct species

Plants that generate extra sets of chromosomes are frequently unable to interbreed with plants that retain the original number of chromosomes, and hence evolve into a(n) \________ over time.

Phylogeny

\________ is the study of the evolutionary history of a species or group.

Adaptive radiation

\________, the development of organisms into diverse species that occupy different ecological niches, can result from speciation.

sexual selection

In animals, \________ can also result in sympatric speciation.

Meteorites

\________ are considered to have battered early Earth.

Morphological evidence

\________ from fossils reveals features that are acquired or lost over time, which may be utilized to build phylogenetic trees.

Human

\________- caused ecological pressures, like as habitat degradation or overhunting, can raise extinction rates.

Prezygotic

\________ or postzygotic reproductive obstacles can induce speciation.

Extinction

\________ (the extinction of all individuals of a species) has occurred throughout Earth's history, as evidenced by the fossil record.

Phylogenetic trees

\________ and cladograms are theories regarding the evolution of organisms across time, with \________ reflecting the approximate timing of evolutionary events.

Postzygotic barriers

\________ exist after the zygote is produced and prevent it from maturing into a viable and fruitful adult organism.

evolution of new species

The \________ is referred to as speciation.

Prezygotic barriers

\________ are impediments that inhibit the creation of a zygote, or fertilized egg.