Evolution Exam Review

These are flashcards to help you study Chapter 24 and 25 for your upcoming exam.

__ is the process by which one species splits, creating a new species which is the source of biologic diversity.

Speciation

consists of changes in allele frequency in a population over time, while refers to broad patterns of evolutionary change above the species level.

Microevolution, macroevolution

Natural selection is the only mechanism of __ evolution, improving the match between organism and environment.

adaptive

The __ defines species by reproductive compatibility.

Biological Species Concept

Within a species, __ can interbreed and produce viable and fertile offspring, holding the species together genetically.

populations

In the Biological Species Concept, the formation of new species relies on __.

reproductive isolation

prevent two species from interbreeding; are the result of successful breeding between two species.

Reproductive isolation/Hybrids

barriers impede mating attempts or prevent successful completion of mating/fertilization. barriers operate after the formation of a hybrid zygote.

Prezygotic, Postzygotic

speciation occurs WITH geographic separation of populations; speciation occurs WITHOUT geographic separation.

Allopatric, Sympatric

Geographic separation can eventually lead to a __ barrier.

Reproductive

Polyploidy is the most common reason for sympatry of __.

plants

__ in Lake Victoria has led to the evolution of over 600 cichlid species due to multiple environmental changes and use of different resources.

Sexual selection

__ reveal factors that cause reproductive isolation and can result in reinforcement, fusion, or stability over time.

Hybrid zones

strengthens reproductive barriers if hybrids are less fit than parent species; weakens reproductive barriers and can lead to gene flow between hybrids and parent populations.

Reinforcement/Fusion

__ shows that different cichlid species can experience fusion in polluted, murky water where females can no longer see color.

Lake Victoria

__Vents might have provided conditions for the creation of life, while __ provided smaller compounds, and __ provided building blocks such as AA, FA, DNA bases, and Sugars.

Alkaline/Volcanoes/Meteorites

__ Experiments demonstrated the abiotic synthesis of small organic molecules under early Earth conditions.

Miller/Urey

The fossil record documents the the history of life, however, it is an ___ record.

incomplete

__ are the earliest fossil evidence of life.

Stromatolites

The fossil record is biased in favor of species that existed for a long time, were abundant/widespread, and contained __ parts.

Hard

rocks are the most abundant source of fossils, and give us insight into the order of life.

Sedimentary/strata

__ are structures that evolve in one context and become co-opted for a different function.

Exaptations

The Geologic Record is categorized into 4 _: Hadean, Archaean, Proterozoic, Phanerozoic

Eons

Events in the history of the planet occurred in the Eon, the Eon, and the __ Eon.

Phanerozoic/Proterozoic/Archean

The __ revolution occurred 2.7 BYA and caused organisms to change.

oxygen

Eukaryotes originated 1.8 BYA by ___, where a bacterium was engulfed by a prokaryotic cell.

Endosymbiosis

Evolution of eukaryotic cells allowed for a greater range of __ forms and increased complexity of organisms.

unicellular

The Ediacaran Period (635 MYA) was the age of __ organisms resembling modern-day sponges and jellyfish.

soft-bodied

The __ Explosion (535 MYA) involved sudden appearances of fossils resembling all modern animal phyla.

Cambrian

Colonization of land occurred around 500 MYA with the appearance of fungi, plants, and then __ .

animals

__ are influenced by Plate Tectonics, Mass Extinctions, and Adaptive Radiations.

Speciation and Extinction

__ drift causes extreme changes in habitat/climate and extreme allopatric speciation.

Continental

__ explains geographic distribution of extinct/extant organisms,

Biogeography

The Permian Mass Extinction (252 MYA) involved extreme __ activity and caused 95% of marine taxa and 70% of terrestrial taxa to perish.

Volcanic

Adaptive radiations follow Mass __, evolution of novel characteristics, and colonization of new regions.

Extinctions

__ is the evolutionary history of a species or group of species and is represented by a branching diagram called a phylogenetic tree.

Phylogeny

Analytical __ classifies diversity and determines relationships.

systematics

__ is the scientific discipline that determines the naming and classification of organisms.

Taxonomy

In Linnaean Taxonomy, each species has a __ scientific name.

two-part

A __ tree includes the most recent common ancestor of all taxa.

Rooted

__ are groups of organisms that share an immediate common ancestor.

Sister taxa

A __ taxon is a lineage that diverges early in evolutionary history.

Basal

Phylogenetic tress can _ around branch points.

rotate

__ is the term referring to existing species at the end of branches.

Extant

is similarities due to shared ancestry, while is similarities due to convergent evolution.

Homology/Analogy

__ uses homologous characteristics as a primary classification criterion for inferring phylogeny.

Cladistics

A __ group consists of a common ancestor and all its descendants.

Clade

A character is an evolutionary novelty unique to a particular taxon, while a character originated in an ancestor of the taxon.

shared derived /shared ancestral

is the species or group of species with a shared derived character, and is a closely related species that diverged before the ingroup.

Ingroup/Outgroup