BIOL 140 Lecture 30: Conservation Biology

Vocabulary terms and definitions from BIOL 140 Lecture 30 covering biodiversity, threats to ecosystems, and conservation strategies.

Genetic Diversity

Genetic variation within and between populations; often linked to adaptations to local conditions.

Species Diversity

The number of species within an ecosystem or across the biosphere.

Ecosystem Diversity

The number of different ecosystems within the biosphere.

Extinction

The local or global loss of a species; can be natural, but current rates are abnormally high due to human activity.

Endangered Species

A species in danger of extinction throughout all or most of its range.

Threatened Species

A species likely to become endangered soon; for example, $22\%$ of known mammals are currently threatened.

Habitat Loss

The #1 driver of biodiversity loss; as habitats disappear, species do as well, causing chain effects on the ecosystem.

Introduced Species

Species intentionally or accidentally brought into a new area that often outcompete natives because natives lack evolved defenses.

Overharvesting

Collecting individuals faster than a population can recover, leading to population crashes such as bluefin tuna reaching less than $20\%$ of their 1980 population size.

Biological Magnification

The process by which toxins become increasingly concentrated at higher trophic levels, such as PCB levels in herring gull eggs being $5,000\times$ higher than phytoplankton.

Nutrient Enrichment

Excess nitrogen and phosphorus leaking into waterways, causing phytoplankton blooms that decompose and create anoxic dead zones.

Biophilia

The human sense of connection to nature and all forms of life; considered an ethical reason to conserve biodiversity.

Ecosystem Services

All processes through which natural ecosystems sustain human life, including flood control, air/water purification, and crop pollination.

Extinction Vortex

A downward spiral toward extinction: small population $ightarrow$ inbreeding and genetic drift $ightarrow$ lower fitness and reproduction $ightarrow$ even smaller population $ightarrow$ extinction.

Minimum Viable Population (MVP)

The minimum effective population size at which a species can survive long-term.

Effective Population Size

The number of individuals actually reproducing in a population; this value is always less than the total population size.

Habitat Fragmentation

The breaking up of continuous habitats into smaller, isolated patches; it harms interior-adapted species but can benefit edge species.

Corridors

Strips of habitat connecting fragmented patches to allow animal movement, gene flow, and migration.

Biodiversity Hot Spots

Geographic areas with exceptionally high species diversity that serve as priority targets for conservation efforts.

Genebanks / Seedbanks

Facilities that store DNA, seeds, or genetic material for assisted reproduction, conservation breeding, or potential cloning.