Biodiversity Flashcards
Biodiversity
the variety of life across all levels of biological organization (genes through ecosystems).
species
a set of organisms that share unique characteristics, can breed, and produce fertile offspring.
_____ describes the number or variety of species found in a region.
Species diversity
_________ describes the number of species.
Species richness
____ or ________describes how much the species differ in numbers of individuals.
Evenness, relative abundance
_______ includes differences in D N A composition among individuals.
Genetic diversity,
Populations with little genetic diversity are more likely to be vulnerable to environmental change, as they lack the variants needed to help adapt to new conditions.
_________ refers to the number and variety of ecosystems, communities, or habitats.
Ecosystem diversity
Species richness generally increases as one approaches the equator, a pattern called ___________.
the latitudinal gradient in species richness.
- Greater geographic area
- More solar energy
- Stability of tropical climates
- Lack of disruptive glaciation events
Species diversity also tends to increase in areas with more _______, such as ecotones.
diverse habitats
Structurally diverse habitats, like forests, also tend to be more ____.
biodiverse
_________ is searching for organisms that might provide new foods, medicines, or other products.
Bioprospecting
This includes animals that are endangered and may go extinct before the substances can be discovered.
Biodiversity increases the _________ of an ecosystem—its ability to withstand disturbance, recover from stress, or adapt to change.
resilience
If a ____________ like a top predator is lost, consequences will cascade down the entire food chain.
keystone species
If an __________ is lost, the entire structure of an ecosystem can change.
ecosystem engineer
A biologist named Edward O. Norton suggested that human beings share an instinctive love for nature and feel an emotional bond with other living things.
He called this _______.
biophilia
Organisms that benefit from ___________ also tend to be geographically widespread, small and fast-reproducing, and lower on the food chain.
human development
As a ________ shrinks, it loses both genetic diversity and geographic range.
population
The United Nations Environment Programme (U N E P) developed the ______________ as a way to express how large the average population size of a species is now compared to a baseline year of 1970.
Living Planet Index
_________ occurs when the last member of a species dies and the entire species ceases to exist.
Extinction
_________ is the loss of a species from one area, but not the entire world.
Extirpation
The _____________ is the pace at which organisms independently go extinct.
background extinction rate
________________ are ones that eliminated at least half of the species on Earth.
Mass extinction events
The International Union for Conservation of Nature (I U C N) maintains the __________, all species facing high risks of extinction.
Red List
This makes habitats ________ and prevents movement of organisms between habitats.
smaller
Habitat loss most commonly occurs through gradual, piecemeal degradation called ____________.
habitat fragmentation
Habitat loss is the primary source of population declines for more than ____ of threatened birds and mammals.
80%
Habitat loss has affected every biome, with _______ being especially threatened.
wetlands
_____ is the illegal killing of wildlife for meat or body parts.
Poaching
_________, non-native species introduced to new environments, can proliferate and displace native species.
Invasive species
Species native to islands are particularly ________, as they have been isolated from new parasites, predators, and competitors.
vulnerable
Climate change is causing some animals to shift their _____ to be closer to the poles or _____ in altitude.
ranges, higher
_____________ is a study that seeks to understand the loss, protection, and restoration of biological diversity.
Conservation biology
____________ determine how small a population can become and how much genetic variation it can lose before encountering inbreeding depression.
Conservation geneticists
By determining this size, they can help wildlife managers make plans for increasing the size of a population.
Small and isolated populations are the most vulnerable, so they get special attention.
The ______________ offers protection to species that fall within two categories:
Endangered Species Act of 1973
_________, or in danger of becoming extinct in the near future
Endangered
The E S A _______ the U.S. government and citizens from taking actions that destroy individuals within identified species.
forbids
____________ plans allow the landowner to harm some individuals of a species if the overall habitat is improved.
Habitat conservation
A _____________- is a promise that the government will not pursue additional action if the landowner pursues actions that assist in the species’ recovery.
safe harbor agreement
The 1973 ____________ bans the international transport of the body parts of rare species.
Convention on International Trade in Endangered Species of Wild Fauna and Flora (C I T E S)
The ___________________ is a treaty that provides funding and incentives for conservation in developing countries.
Convention on Biological Diversity
Zoos and botanical gardens have become centers for __________, where endangered individuals such as black rhinos are bred and raised with the intention of reintroducing their progeny into the wild.
captive breeding
__________ is the analysis of evidence to make an identification or answer a question relating to a crime.
Forensic science
Conservation biologists are using forensics to trace the geographic origin of organisms or body parts recovered from _______
the black market.
The protection of __________ helps to protect many others.
umbrella species
Environmental organizations use large charismatic vertebrates as _________ to promote conservation.
flagship species
_____________ are regions that support a great number of species that are found nowhere else.
Biodiversity hotspots
convergent evolution
the independent development of similar traits or features (as of body structure or behavior) in unrelated or distantly related species or lineages that typically occupy similar environments or ecological niches.
The process by which new species are generated is termed ________.
speciation
Allopatric speciation
occurs when a species separates into two separate groups that are isolated from one another. A physical barrier, such as a mountain range or a waterway, makes it impossible for them to breed with one another.
