Bio lec 14

Hickory Horned Devil

The caterpillar of the Regal Moth, known as the largest caterpillar in North America.

Microevolution

Generation-to-generation change in a population’s frequencies of alleles.

Macroevolution

Major biological changes, including the formation of new species.

Biological Species Concept

Defines species as groups of interbreeding natural populations that are reproductively isolated from other such groups.

Reproductive Isolation

Prevents closely related species from interbreeding.

Pre-zygotic isolating mechanisms

Prevent the formation of a zygote.

Post-zygotic isolation

Prevents hybrid offspring from developing or reproducing.

Allopatric Speciation

Origin of new species due to geographic barriers preventing gene flow.

Sympatric Speciation

Origin of new species without geographic isolation, often due to genetic mutation.

Polyploidy

A genetic condition causing an individual to have an extra set of chromosomes, making it reproductively incompatible with the parent species.

Gradualism

Proposes a continuous, slow accumulation of changes over a very long time.

Punctuated Equilibrium

Suggests that most species-defining characteristics change over a relatively short period, involving bursts of change followed by long periods of stasis.

Taxonomy

The system by which organisms are classified based on their evolutionary relationships.

Binomial nomenclature

A two-part scientific name for each species, consisting of the Genus name and the Specific Epithet.

Geological Time Scale

A timeline representing key events in Earth's history and the evolution of life.

Biogeography

The study of past and present distribution of organisms.

Homeotic genes

Master control genes that program development and affect the rate, timing, and spatial pattern of organisms' development.

Paedomorphosis

The retention of juvenile features in the adult form of an organism.

Exaptations

Structures that evolve in one context but are co-opted for another function.

Complex eyes evolution

Describes the incremental modifications that lead to the evolution of complex visual systems.