54.1 What is Biodiversity?

In essence, biodiversity means biological diversity.
Genetic diversity is the total genetic information contained within all individuals of a population, species, or group of species.
- Genome sequencing is a research protocol that sequences the entire genome of multiple members of the same species.
- Environmentαl sequencing is a research protocol that sequences all or most of the genes and/or alleles present in a sample taken from the soil or water present in a habitat (or your gut).
- Genetic diversity is important because it represents the adaptive capacity of a population or higher taxonomic group一the ability of that group to persist over time.
The diversity of species present is a key feature of biological communities. It is usually qualified in two ways:
- Species richness is a count of how many species are present in a defined area (which may vary in size from local to regional).
- Species diversity is a weighted measure that incorporates both species richness and evenness, the relative abundance of each species present.
One new technique for identifying species is called DNA barcoding-the use of well-characterized gene sequences to distinguish species.
- The idea is that variation in one gene is higher between species than within species.
Thus, ecologists increasingly turn to newer measures of diversity at the species level:
- Phylogenetic diversity; In terms of evolution, some species give a community evolutionary distinctiveness because they are phylogenetically distant from other species.
- Functional diversity; In terms of ecology, some species have functional traits that play a key role in the function of an ecosystem.
Ecosystem diversity is a measure of these complex factors plus interactions with the abiotic environment.
Intertwined with the concept of ecosystem diversity is ecosystem function, which refers to the sum of biological and chemical processes that are characteristic of a given ecosystem-such as primary production, nitrogen cycling, decomposition, and carbon storage.
In 1988, conservation biologist Norman Myers pioneered the term biodiversity hotspot to characterize regions that are in most urgent need of conservation action-areas where efforts to preserve habitat would have the highest return on investment.

54.2 Threats to Biodiversity and Ecosystem Function

An endangered species is a species whose numbers have decreased so drastically that it is almost certain to go extinct unless effective conservation programs are put in place.
Humans cause habitat destruction, the physical and functional loss of habitats, by many methods:
- Logging and burning forests
- Damming rivers
- Dredging or filling estuaries and wetlands
- Plowing prairies and grazing livestock
- Excavating minerals and fuels
- Building housing developments, golf courses, shopping centers, office complexes, airports, roads, and other structures
Aside from destroying natural areas outright, human activities can also cause habitat degradation, a reduction in the quality of a habitat. Humans can degrade habitats in many ways, for example:
- Artificial lights disorient migrants and disrupt night foraging.
- Traffic noise interrupts communication and causes stress.
- Pet cats have contributed to at least 63 vertebrate extinctions.
One of the most pervasive patterns of habitat degradation is habitat fragmentation-dividing contiguous areas of natural habitats into small, isolated fragments.
Overexploitation refers to any unsustainable removal of organisms from the natural environment for use by humans.
- Overexploitation is especially important in marine environments.
A nonnative species that are introduced into a new area is called an exotic species.
- Exotic species do not necessarily pose problems, and they can even be beneficial in some circumstances.
- But some exotic species directly threaten native species by eating them, competing with them, causing disease, or other types of deleterious interactions.
If an exotic species is introduced to a new area, grows to large population size, and disrupts species native to the area, it is called an invasive species.
Given reasonable projections of how much habitat will be lost over a given time period, biologists can estimate rates of extinction based on species-area relationships.
- The concept here is to track backward on a species-area curve.

54.3 Why Are Biodiversity and Ecosystem Function Important?

Resistance is a measure of the extent to which a community remains unchanged during a disturbance.
Resilience is a measure of how quickly a community recovers following a disturbance.
A natural experiment occurs when comparison groups are created by an unplanned, unmanipulated change in conditions.
Considered collectively, all the direct and indirect benefits that humans derive from organisms and the ecosystems they compose are called ecosystem services.
Bioprospecting is the exploration of bacteria, archaea, protists, plants, fungi, and animals as novel sources of drugs or ingredients in consumer products-has benefited from the recent explosion of genetic information.

54.4 Preserving Biodiversity and Ecosystem Function

The way forward involves both reducing population growth and improving sustainability-the managed use of resources at a rate only as high as the rate at which they are replaced.
Agricultural scientists are racing to preserve diverse strains of crop and wild plants in seed banks-long-term storage facilities to avoid the loss of genetic diversity in local and global populations.
Some species-including Pere David’s deer and the northern white rhinoceros are extinct in the wild and exist only in captivity.
- These animals are examples of ex situ conservation, the preservation of species in zoos, aquaria, or other artificial settings.
One long-term solution to enabling gene flow among isolated populations is the establishment of wildlife corridors, strips of undeveloped habitat that connect preserved areas.

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Chapter 54: Biodiversity and Conservation Biology

The growing field of conservation biology is making progress in studying, preserving, and restoring biodiversity.

54.1 What is Biodiversity?

In essence, biodiversity means biological diversity.
Genetic diversity is the total genetic information contained within all individuals of a population, species, or group of species.
- Genome sequencing is a research protocol that sequences the entire genome of multiple members of the same species.
- Environmentαl sequencing is a research protocol that sequences all or most of the genes and/or alleles present in a sample taken from the soil or water present in a habitat (or your gut).
- Genetic diversity is important because it represents the adaptive capacity of a population or higher taxonomic group一the ability of that group to persist over time.
The diversity of species present is a key feature of biological communities. It is usually qualified in two ways:
- Species richness is a count of how many species are present in a defined area (which may vary in size from local to regional).
- Species diversity is a weighted measure that incorporates both species richness and evenness, the relative abundance of each species present.
One new technique for identifying species is called DNA barcoding-the use of well-characterized gene sequences to distinguish species.
- The idea is that variation in one gene is higher between species than within species.
Thus, ecologists increasingly turn to newer measures of diversity at the species level:
- Phylogenetic diversity; In terms of evolution, some species give a community evolutionary distinctiveness because they are phylogenetically distant from other species.
- Functional diversity; In terms of ecology, some species have functional traits that play a key role in the function of an ecosystem.
Ecosystem diversity is a measure of these complex factors plus interactions with the abiotic environment.
Intertwined with the concept of ecosystem diversity is ecosystem function, which refers to the sum of biological and chemical processes that are characteristic of a given ecosystem-such as primary production, nitrogen cycling, decomposition, and carbon storage.
In 1988, conservation biologist Norman Myers pioneered the term biodiversity hotspot to characterize regions that are in most urgent need of conservation action-areas where efforts to preserve habitat would have the highest return on investment.

54.2 Threats to Biodiversity and Ecosystem Function

An endangered species is a species whose numbers have decreased so drastically that it is almost certain to go extinct unless effective conservation programs are put in place.
Humans cause habitat destruction, the physical and functional loss of habitats, by many methods:
- Logging and burning forests
- Damming rivers
- Dredging or filling estuaries and wetlands
- Plowing prairies and grazing livestock
- Excavating minerals and fuels
- Building housing developments, golf courses, shopping centers, office complexes, airports, roads, and other structures
Aside from destroying natural areas outright, human activities can also cause habitat degradation, a reduction in the quality of a habitat. Humans can degrade habitats in many ways, for example:
- Artificial lights disorient migrants and disrupt night foraging.
- Traffic noise interrupts communication and causes stress.
- Pet cats have contributed to at least 63 vertebrate extinctions.
One of the most pervasive patterns of habitat degradation is habitat fragmentation-dividing contiguous areas of natural habitats into small, isolated fragments.
Overexploitation refers to any unsustainable removal of organisms from the natural environment for use by humans.
- Overexploitation is especially important in marine environments.
A nonnative species that are introduced into a new area is called an exotic species.
- Exotic species do not necessarily pose problems, and they can even be beneficial in some circumstances.
- But some exotic species directly threaten native species by eating them, competing with them, causing disease, or other types of deleterious interactions.
If an exotic species is introduced to a new area, grows to large population size, and disrupts species native to the area, it is called an invasive species.
Given reasonable projections of how much habitat will be lost over a given time period, biologists can estimate rates of extinction based on species-area relationships.
- The concept here is to track backward on a species-area curve.

54.3 Why Are Biodiversity and Ecosystem Function Important?

Resistance is a measure of the extent to which a community remains unchanged during a disturbance.
Resilience is a measure of how quickly a community recovers following a disturbance.
A natural experiment occurs when comparison groups are created by an unplanned, unmanipulated change in conditions.
Considered collectively, all the direct and indirect benefits that humans derive from organisms and the ecosystems they compose are called ecosystem services.
Bioprospecting is the exploration of bacteria, archaea, protists, plants, fungi, and animals as novel sources of drugs or ingredients in consumer products-has benefited from the recent explosion of genetic information.

54.4 Preserving Biodiversity and Ecosystem Function

The way forward involves both reducing population growth and improving sustainability-the managed use of resources at a rate only as high as the rate at which they are replaced.
Agricultural scientists are racing to preserve diverse strains of crop and wild plants in seed banks-long-term storage facilities to avoid the loss of genetic diversity in local and global populations.
Some species-including Pere David’s deer and the northern white rhinoceros are extinct in the wild and exist only in captivity.
- These animals are examples of ex situ conservation, the preservation of species in zoos, aquaria, or other artificial settings.
One long-term solution to enabling gene flow among isolated populations is the establishment of wildlife corridors, strips of undeveloped habitat that connect preserved areas.