Biodiversity and Conservation BIO 47 by Owen Borville October 2, 2025
Biodiversity is the number of species present in the biosphere. Biodiversity has been measured by taking into account the number of species and their relative abundance to each other.
Adaptive radiation is when a single species quickly gives rise to many new species, each specializing in a different way of life or environment, often in isolated ecosystems.
Extinction is the disappearance of a species, often because of a large predator. A mass extinction is a significant global event where many different species disappear within a short time period, often because of a catastrophic event and as observed in the fossil record. Mass extinctions are largely impacted by large natural catastrophic events, human activity, and new predators that destroy habitats and introduce new species that are harmful.
Genetic diversity or genetic variation allows species to have the abilities to survive their environments. Genetic diversity can also be measured as chemical diversity because different species produce different chemicals in their cells, including proteins, products and byproducts of metabolism.
Human activities are causing losses in diversity around the world as cities grow and agriculture expands.
Ecosystem diversity is the number of different ecosystems on the planet or within a geographic area. Whole ecosystems can be lost due to human activity. Some species of a destroyed ecosystem can survive by moving to other existing ecosystems. When an ecosystem is lost, interactions between species are lost, along with the loss of unique features of coadaptation, and the loss of biological productivity from an ecosystem. An example of a large nearly extinct ecosystem in North America is the prairie ecosystem, which was destroyed by human development of cities and agriculture. Despite being nearly extinct, conservation efforts are underway to preserve this ecosystem, including the native soils.
Knowing the species diversity on Earth will always be limited because of the lack of financial resources to do so. There are almost 1.5 million living species described and over 10 million predicted. Most of these species are in the Animalia kingdom with over one million and Kingdom Plantae is second.
Despite many living species being described, up to 20,000 new species are being discovered every year and describing every species on earth could take up to five centuries to complete.
Endemic species are found only in one location, as biodiversity is not evenly distributed on Earth. Endemic species are very restricted and vulnerable to extinction.
Biogeography is the study of the distribution of the world's living species in the past and present. Biogeographers study both biology and ecology, along with soil science, and climatology. Biogeographers can focus on current ecology of plants and animals, the past distribution of living species, or the conservation of species.
One of the first observed patterns in ecology is that species diversity increases toward the equator of Earth. The reason is not known but, it could be because more intense heat in the tropics regions versus the temperate and polar regions. Tropical ecosystem complexity may promote speciation by increasing the heterogeneity or number of ecological niches in the tropics versus the higher latitudes. Also, the tropics regions were less impacted by the ice age glaciation, and have had more time to diversify than locations away from the tropics. The tropics also have more stable weather throughout the year than temperate regions that help promote speciation and diversity, even with the rainy season. Tropics have more endemic species than other regions but knowledge of these species is very low, unfortunately.
Biodiversity hot spots are geographic areas that contain high numbers of endemic species and these areas are focal points for conservation efforts. Today, there are 34 biodiversity hot spots in the world, which cover only 2.3 percent of the Earth's surface but contain up to half of world's plant and animal species. These locations include California and Mexico in North America, the western coast of South America, much of eastern Brazil, the Mediterranean region of Europe and western North Africa, west Africa, south Africa, east Africa, Central and west Asia, India, southeast Asia, Japan, western Australia, and New Zealand.
Extinction rates of many living organisms are difficult to determine because of the number of species in existence and the remoteness of these species.
The species-area relationship is the rate at which new species are seen when the area surveyed is increased.
The importance of biodiversity to human life is that the human species cannot exist without a supportive ecosystem for basic needs, including food, medicine, clean water, and resources to build cities and living spaces.
Many plant species on Earth provide important medicines for human health. Most plants produce secondary plant compounds which are toxins used to protect the plant from insects and other animals that eat them, but some of which also work as medication.
Despite the emergence of synthetic medicines being developed to replace plant medicines, many medicines are still derived from natural plant ingredients, as much as 10 percent. In addition, antibiotic medications are compounds largely derived from fungi and bacteria.
Recently, animal venoms and poisons have been research for possible medicinal potential to treat human diseases. Some drugs have been approved by the federal government that are derived from animal toxins and more are under research. Venomous reptiles, amphibians, marine invertebrates, and even some mammals are under research for possible medicinal potential.
If these animal or plant species become extinct, there will be fewer opportunities to find medicinal cures for human diseases. About one third of pharmaceutical research is spent on natural compounds and also about one third of new drugs introduced to the market have been from natural compounds.
Humans have been breeding selected agricultural crop varieties throughout history. Low crop diversity can lead to a single crop being wiped out with few alternatives for the food supply. An example is the Irish potato famine. Therefore developing a diversity of crops is extremely important for the food supply for human civilization. A diversity of crops can better withstand new pests in crops and provide abundant food supply.
Crop biodiversity can result in disease resistance and lack of diversity in crop species can also have similar risks. The ability to create new crop varieties relies on the diversity of varieties available and the accessibility of wild forms of the crop plant. The wild forms of the crop often are the source of new gene variants that can be bred with existing varieties to create new varieties. Loss of wild species of a crop will cause the loss of potential in crop improvement. Therefore, maintaining the genetic diversity of wild species of domestic species helps maintain the food supply for humans. In the 20th century, seed banks of crop varieties have been used to maintain crop diversity.
Crop success is largely dependent on the quality of the soil. Most soils contain a large diversity of organisms that maintain nutrient cycles like breaking down organic matter into nutrient compounds that crops need for growth. These organisms also maintain soil texture that affects water and oxygen dynamics in the soil that are necessary for plant growth. These processes are known as ecosystem services and they occur within ecosystems in the soil and other ecosystems because of the diversity of the organisms and their activities that live there and they provide benefits to human food production, drinking water, and clean air.
Plant pollination is another important ecosystem service from bees, insects, and birds, providing a huge benefit. If the population or diversity of any of these species was reduced, the impact on human food supply would be very large.
Pesticide chemicals help control and stop pests like insects from damaging crop supplies. However, pesticides are expensive, and insects can become immune to pesticides. In addition, pesticides can also kill non-pest species and risk the health of consumers and agricultural workers. Predators of pests can have similar effectiveness of limiting pests than pesticides, however, without the side effects of pesticides.
In addition to land crops, many food sources come from fish and aquatic environments like freshwater and marine. However, the global fish production has declined in recent history, which impacts the food supply for humans. Losing these food sources would have a dramatic effect on the human civilizations that depend on them.
Researchers have shown that humans benefit psychologically from living in a biodiverse world and natural landscapes. Therefore, the absence of biodiversity and natural landscapes in the world could have a negative effect on humans.
Threats to biodiversity are of major concern, the greatest of which is human activities, human population growth, and resource exploitation. Humans require resources to survive and grow, and these resources are being removed unsustainably from the environment.
The three greatest proximate threats to biodiversity are habitat loss, overharvesting, and introduction of exotic species. Climate change is also a major threat to biodiversity. The burning of fossil fuels to benefit humans is also a major threat to biodiversity, in addition to toxic pollution.
Habitat loss is a result of human activities and causes the eventual elimination of a species habitat and ultimately the species itself. In the tropics, habitat loss leads not only to species extinction, but also endemism, where a species is only found in one habitat or ecosystem and the elimination of this ecosystem, will eliminate the entire species because it is not found anywhere else on Earth. Species listed as endangered or near extinction are the orangutan of Sumatra and Borneo, the Sumatran tiger and elephant. These species live in forests that are being removed for timber and to plant palm oil plantations. Timber sold at many hardware stores in the U.S. are being extracted from these types of ecosystems with endemic species, up to 10 percent of timber is illegally logged according to some estimates.
Habitat destruction can affect other ecosystems in addition to forests. Rivers and streams are very important ecosystems that are often impacted by human activities such as land development, damming, channelizing, or water removal. These activities affect water flow, and soil erosion from forest removal can affect species that live there by removing fertile nutrients from the soil and causing river water to become toxic. Conservation efforts have included replanting trees where they have been removed.
Overharvesting of species is an issue, particularly for aquatic species such as the Atlantic cod fish species. The species is overharvested for business reasons as a food resource, but often these species are overharvested so that the species is nearly wiped out or extinct to as much as one percent of previous populations. The species are overharvested to such an extent that the species cannot reproduce and replenish their populations to a healthy level. The fisheries collapse because of overharvesting. New regulation efforts have been proposed to prevent overharvesting. Other examples of overharvesting include elephants for ivory, whales for oil, rhinos for horns, pangolins for scales and meat, and some fish species like tuna. Some plants have been overharvested for medicinal purposes. The passenger pigeon has been over harvested as a game bird. Steller's sea cow was overharvested for its meat.
While fishery extinction does not always lead to biological extinction, it is still harmful to the fish species and their ecosystems. Whales and other slow-growth aquatic species are more in danger of extinction. Harvesting of diverse aquatic species for the pet industry has also led to population decline, in addition to amphibians, reptiles, birds, plants, and some mammals. Coral reef ecosystems face species declines due to pet harvesting.
Bush meat refers to the meat of wild land animals killed for food by human hunters, and many species are under threat of extinction in African and Asia. Bush meat was originally used to feed families directly, however recent commercialization of the meat industry has led to unsustainable levels of harvesting.
Exotic species are non-native species that have been introduced to a new ecosystem. The kudzu plant is native to Japan but was introduced to the United States in the late 19th century for soil conservation. However, the kudzu grew too well and it became an invasive pest species as it covers over seven million acres in the southeast U.S.
Human transportation of people and goods through trade, including species, has dramatically increased the introduction of species into new ecosystems around the world. Some of these new ecosystems have few predators and allow exotic species to grow and thrive there.
Many exotic species fail because of the small number of individual species introduced or poor adaptation to the new ecosystem. Other exotic species have the abilities to thrive in a new environment and have a large population increase. Exotic species can threaten the existing species in an ecosystem and are referred to as invasive species. Exotic species threaten other species through competition for resources, predation, or disease. In addition, some exotic species introduced to a new ecosystem can bring some benefits such as a new food supply for pollinating insects and other species in the ecosystem.
Lakes and islands are especially harmed by exotic species and can cause extinction of native species or threaten native species as the new species competes with the native species for resources. Sometimes the introduction of an exotic or new species can be accidental or natural, but often new species are introduced intentionally by humans, with harmful effects. Examples include the intentional introduction of the Nile perch and the accidental introduction of the brown tree snake to Guam. Sometimes a fungus, for example, is spread unintentionally in the world by transport and harms amphibian species among others by causing disease. The amphibian species in turn can be an invasive species and spread the fungus causing even more harm to the ecosystem. Another fungus pathogen has been responsible for infecting bats in Eastern North America and the reason or cause of the spread is unknown.
Climate change, particularly the climate change caused by human activity, is responsible for warming trends that harm and threaten certain species. Climate change can cause certain species to move or migrate, and different species come into conflict with each other by competing for the same resources. Migration can even cause different species to mate with each other as they cross paths, which can alter the ecosystem in a harmful way as the offspring may not be able to adapt to the ecosystem.
Migration shifts have been observed in bird species, plants, butterflies, insects, freshwater fishes, reptiles, and mammals. Climate change patterns can change the conditions of ecosystems, which can threaten the species that live in a particular ecosystem. Warmer climate can also be associated with more precipitation or colder climate can be associated with more snowfall and ice.
Rising temperatures cause sea level to rise, which can threaten coastal ecosystems. The melting of ice in polar ecosystems can also threaten ecosystems in a negative way, in addition to expanding ice.
Measuring biodiversity is being done through the technology of molecular genetics. DNA barcoding is one molecular genetic method to identify species using the sequence of portions of the gene. Rapid sequencing machines greatly aid the effort and quicken the process and computer resources help store large volumes of data.
Computer databases today can provide information about many species and allow new species to be added to the database. However, the database is not complete. In addition, endangered species are labeled in the database and to what known degree these species are threatened, known as the "Red List". The non-profit group IUCN helps update the database. The database is incomplete and information is continually being added.
Government legislation in many nations has been passed to help protect species from endangerment. This legislation includes international treaties, national and state laws. This legislation limits certain species from being transported across nation's borders. The Endangered Species Act in the U.S. was created in 1973 to protect endangered species and regulate hunting and fishing activities. Additional legislation has been approved to protect migratory birds in North America from hunting activities with the Migratory Bird Treaty Act (MBTA).
Private non-profit organizations also help in conservation efforts of species, such as the Nature Conservancy. The Paris Climate Agreement aims to halt or limit global temperature rise and was signed by over 194 countries, making it the largest unified world effort to reduce greenhouse gas emissions and embrace alternative energy sources to help prevent damage to ecosystems from climate change.
Conservation efforts also include establishment of wildlife and ecosystem preserves, which are specific areas of land where living species reside that are protected in some way from human activity. Scientists debate with lawmakers about how much land should be protected and to what extent. A 2003 estimate shows that 11.5 percent of Earth's land surface was covered by conservation preserves of some kind. However, these preserves do not protect all endangered species and more work is needed to determine what lands need to be preserved, or what species need to be preserved and to what degree they need to be preserved. Researchers insist that more work needs to be done at preserves to protect biodiversity.
Preserves perform better when there are buffer zones around them which allow organisms to exit the boundaries of the preserve without immediate negative consequences from predation or lack of resources. One large preserve is better than several smaller preserves because more of the habitat is unaffected by the edges. In addition, preserves with a square or circular shape are better than preserves with many thin arms for the same reason. If smaller preserves are necessary, wildlife corridors can be created between them so that individuals can move between the preserves and help connect the smaller preserves together. Wildlife corridors can be created along streams, vegetated strips, or man-made bridges. Connecting smaller preserves together allows them to behave like one larger preserve, which is beneficial to the species in the ecosystem.
Limitations of preserves for conservation efforts include political and economic pressures that usually reduce the size of preserves. In addition, establishing proper buffers around the preserve can be politically difficult. Climate change can cause species withing the preserves to migrate out of the preserve, and therefore conservationists are planning for the future effects of climate change.
A keystone species is a species that is instrumental in maintaining biodiversity in an ecosystem. Removing a keystone species from an ecological community may cause imbalance or a collapse in diversity. Examples of keystone species around the world are wolves, starfish, corals, bees, eagles, and vultures.
Recent conservation experiments involve removing aging dams from rivers and streams to restore the naturally fluctuating water levels to increase biodiversity and improved water quality.
Conservation efforts of zoos involve captive breeding programs of species and conservation education. The results of captive breeding have been mixed, but there has been some success of preserving species and preventing endangerment or extinction. In addition, there are not enough zoo facilities in the world to establish captive breeding programs for all of the species that are currently at risk. The results of the effort to educate the public about conservation of species has also been mixed as the world becomes more urbanized and humans are less connected with wildlife than in the past.
Biodiversity is the number of species present in the biosphere. Biodiversity has been measured by taking into account the number of species and their relative abundance to each other.
Adaptive radiation is when a single species quickly gives rise to many new species, each specializing in a different way of life or environment, often in isolated ecosystems.
Extinction is the disappearance of a species, often because of a large predator. A mass extinction is a significant global event where many different species disappear within a short time period, often because of a catastrophic event and as observed in the fossil record. Mass extinctions are largely impacted by large natural catastrophic events, human activity, and new predators that destroy habitats and introduce new species that are harmful.
Genetic diversity or genetic variation allows species to have the abilities to survive their environments. Genetic diversity can also be measured as chemical diversity because different species produce different chemicals in their cells, including proteins, products and byproducts of metabolism.
Human activities are causing losses in diversity around the world as cities grow and agriculture expands.
Ecosystem diversity is the number of different ecosystems on the planet or within a geographic area. Whole ecosystems can be lost due to human activity. Some species of a destroyed ecosystem can survive by moving to other existing ecosystems. When an ecosystem is lost, interactions between species are lost, along with the loss of unique features of coadaptation, and the loss of biological productivity from an ecosystem. An example of a large nearly extinct ecosystem in North America is the prairie ecosystem, which was destroyed by human development of cities and agriculture. Despite being nearly extinct, conservation efforts are underway to preserve this ecosystem, including the native soils.
Knowing the species diversity on Earth will always be limited because of the lack of financial resources to do so. There are almost 1.5 million living species described and over 10 million predicted. Most of these species are in the Animalia kingdom with over one million and Kingdom Plantae is second.
Despite many living species being described, up to 20,000 new species are being discovered every year and describing every species on earth could take up to five centuries to complete.
Endemic species are found only in one location, as biodiversity is not evenly distributed on Earth. Endemic species are very restricted and vulnerable to extinction.
Biogeography is the study of the distribution of the world's living species in the past and present. Biogeographers study both biology and ecology, along with soil science, and climatology. Biogeographers can focus on current ecology of plants and animals, the past distribution of living species, or the conservation of species.
One of the first observed patterns in ecology is that species diversity increases toward the equator of Earth. The reason is not known but, it could be because more intense heat in the tropics regions versus the temperate and polar regions. Tropical ecosystem complexity may promote speciation by increasing the heterogeneity or number of ecological niches in the tropics versus the higher latitudes. Also, the tropics regions were less impacted by the ice age glaciation, and have had more time to diversify than locations away from the tropics. The tropics also have more stable weather throughout the year than temperate regions that help promote speciation and diversity, even with the rainy season. Tropics have more endemic species than other regions but knowledge of these species is very low, unfortunately.
Biodiversity hot spots are geographic areas that contain high numbers of endemic species and these areas are focal points for conservation efforts. Today, there are 34 biodiversity hot spots in the world, which cover only 2.3 percent of the Earth's surface but contain up to half of world's plant and animal species. These locations include California and Mexico in North America, the western coast of South America, much of eastern Brazil, the Mediterranean region of Europe and western North Africa, west Africa, south Africa, east Africa, Central and west Asia, India, southeast Asia, Japan, western Australia, and New Zealand.
Extinction rates of many living organisms are difficult to determine because of the number of species in existence and the remoteness of these species.
The species-area relationship is the rate at which new species are seen when the area surveyed is increased.
The importance of biodiversity to human life is that the human species cannot exist without a supportive ecosystem for basic needs, including food, medicine, clean water, and resources to build cities and living spaces.
Many plant species on Earth provide important medicines for human health. Most plants produce secondary plant compounds which are toxins used to protect the plant from insects and other animals that eat them, but some of which also work as medication.
Despite the emergence of synthetic medicines being developed to replace plant medicines, many medicines are still derived from natural plant ingredients, as much as 10 percent. In addition, antibiotic medications are compounds largely derived from fungi and bacteria.
Recently, animal venoms and poisons have been research for possible medicinal potential to treat human diseases. Some drugs have been approved by the federal government that are derived from animal toxins and more are under research. Venomous reptiles, amphibians, marine invertebrates, and even some mammals are under research for possible medicinal potential.
If these animal or plant species become extinct, there will be fewer opportunities to find medicinal cures for human diseases. About one third of pharmaceutical research is spent on natural compounds and also about one third of new drugs introduced to the market have been from natural compounds.
Humans have been breeding selected agricultural crop varieties throughout history. Low crop diversity can lead to a single crop being wiped out with few alternatives for the food supply. An example is the Irish potato famine. Therefore developing a diversity of crops is extremely important for the food supply for human civilization. A diversity of crops can better withstand new pests in crops and provide abundant food supply.
Crop biodiversity can result in disease resistance and lack of diversity in crop species can also have similar risks. The ability to create new crop varieties relies on the diversity of varieties available and the accessibility of wild forms of the crop plant. The wild forms of the crop often are the source of new gene variants that can be bred with existing varieties to create new varieties. Loss of wild species of a crop will cause the loss of potential in crop improvement. Therefore, maintaining the genetic diversity of wild species of domestic species helps maintain the food supply for humans. In the 20th century, seed banks of crop varieties have been used to maintain crop diversity.
Crop success is largely dependent on the quality of the soil. Most soils contain a large diversity of organisms that maintain nutrient cycles like breaking down organic matter into nutrient compounds that crops need for growth. These organisms also maintain soil texture that affects water and oxygen dynamics in the soil that are necessary for plant growth. These processes are known as ecosystem services and they occur within ecosystems in the soil and other ecosystems because of the diversity of the organisms and their activities that live there and they provide benefits to human food production, drinking water, and clean air.
Plant pollination is another important ecosystem service from bees, insects, and birds, providing a huge benefit. If the population or diversity of any of these species was reduced, the impact on human food supply would be very large.
Pesticide chemicals help control and stop pests like insects from damaging crop supplies. However, pesticides are expensive, and insects can become immune to pesticides. In addition, pesticides can also kill non-pest species and risk the health of consumers and agricultural workers. Predators of pests can have similar effectiveness of limiting pests than pesticides, however, without the side effects of pesticides.
In addition to land crops, many food sources come from fish and aquatic environments like freshwater and marine. However, the global fish production has declined in recent history, which impacts the food supply for humans. Losing these food sources would have a dramatic effect on the human civilizations that depend on them.
Researchers have shown that humans benefit psychologically from living in a biodiverse world and natural landscapes. Therefore, the absence of biodiversity and natural landscapes in the world could have a negative effect on humans.
Threats to biodiversity are of major concern, the greatest of which is human activities, human population growth, and resource exploitation. Humans require resources to survive and grow, and these resources are being removed unsustainably from the environment.
The three greatest proximate threats to biodiversity are habitat loss, overharvesting, and introduction of exotic species. Climate change is also a major threat to biodiversity. The burning of fossil fuels to benefit humans is also a major threat to biodiversity, in addition to toxic pollution.
Habitat loss is a result of human activities and causes the eventual elimination of a species habitat and ultimately the species itself. In the tropics, habitat loss leads not only to species extinction, but also endemism, where a species is only found in one habitat or ecosystem and the elimination of this ecosystem, will eliminate the entire species because it is not found anywhere else on Earth. Species listed as endangered or near extinction are the orangutan of Sumatra and Borneo, the Sumatran tiger and elephant. These species live in forests that are being removed for timber and to plant palm oil plantations. Timber sold at many hardware stores in the U.S. are being extracted from these types of ecosystems with endemic species, up to 10 percent of timber is illegally logged according to some estimates.
Habitat destruction can affect other ecosystems in addition to forests. Rivers and streams are very important ecosystems that are often impacted by human activities such as land development, damming, channelizing, or water removal. These activities affect water flow, and soil erosion from forest removal can affect species that live there by removing fertile nutrients from the soil and causing river water to become toxic. Conservation efforts have included replanting trees where they have been removed.
Overharvesting of species is an issue, particularly for aquatic species such as the Atlantic cod fish species. The species is overharvested for business reasons as a food resource, but often these species are overharvested so that the species is nearly wiped out or extinct to as much as one percent of previous populations. The species are overharvested to such an extent that the species cannot reproduce and replenish their populations to a healthy level. The fisheries collapse because of overharvesting. New regulation efforts have been proposed to prevent overharvesting. Other examples of overharvesting include elephants for ivory, whales for oil, rhinos for horns, pangolins for scales and meat, and some fish species like tuna. Some plants have been overharvested for medicinal purposes. The passenger pigeon has been over harvested as a game bird. Steller's sea cow was overharvested for its meat.
While fishery extinction does not always lead to biological extinction, it is still harmful to the fish species and their ecosystems. Whales and other slow-growth aquatic species are more in danger of extinction. Harvesting of diverse aquatic species for the pet industry has also led to population decline, in addition to amphibians, reptiles, birds, plants, and some mammals. Coral reef ecosystems face species declines due to pet harvesting.
Bush meat refers to the meat of wild land animals killed for food by human hunters, and many species are under threat of extinction in African and Asia. Bush meat was originally used to feed families directly, however recent commercialization of the meat industry has led to unsustainable levels of harvesting.
Exotic species are non-native species that have been introduced to a new ecosystem. The kudzu plant is native to Japan but was introduced to the United States in the late 19th century for soil conservation. However, the kudzu grew too well and it became an invasive pest species as it covers over seven million acres in the southeast U.S.
Human transportation of people and goods through trade, including species, has dramatically increased the introduction of species into new ecosystems around the world. Some of these new ecosystems have few predators and allow exotic species to grow and thrive there.
Many exotic species fail because of the small number of individual species introduced or poor adaptation to the new ecosystem. Other exotic species have the abilities to thrive in a new environment and have a large population increase. Exotic species can threaten the existing species in an ecosystem and are referred to as invasive species. Exotic species threaten other species through competition for resources, predation, or disease. In addition, some exotic species introduced to a new ecosystem can bring some benefits such as a new food supply for pollinating insects and other species in the ecosystem.
Lakes and islands are especially harmed by exotic species and can cause extinction of native species or threaten native species as the new species competes with the native species for resources. Sometimes the introduction of an exotic or new species can be accidental or natural, but often new species are introduced intentionally by humans, with harmful effects. Examples include the intentional introduction of the Nile perch and the accidental introduction of the brown tree snake to Guam. Sometimes a fungus, for example, is spread unintentionally in the world by transport and harms amphibian species among others by causing disease. The amphibian species in turn can be an invasive species and spread the fungus causing even more harm to the ecosystem. Another fungus pathogen has been responsible for infecting bats in Eastern North America and the reason or cause of the spread is unknown.
Climate change, particularly the climate change caused by human activity, is responsible for warming trends that harm and threaten certain species. Climate change can cause certain species to move or migrate, and different species come into conflict with each other by competing for the same resources. Migration can even cause different species to mate with each other as they cross paths, which can alter the ecosystem in a harmful way as the offspring may not be able to adapt to the ecosystem.
Migration shifts have been observed in bird species, plants, butterflies, insects, freshwater fishes, reptiles, and mammals. Climate change patterns can change the conditions of ecosystems, which can threaten the species that live in a particular ecosystem. Warmer climate can also be associated with more precipitation or colder climate can be associated with more snowfall and ice.
Rising temperatures cause sea level to rise, which can threaten coastal ecosystems. The melting of ice in polar ecosystems can also threaten ecosystems in a negative way, in addition to expanding ice.
Measuring biodiversity is being done through the technology of molecular genetics. DNA barcoding is one molecular genetic method to identify species using the sequence of portions of the gene. Rapid sequencing machines greatly aid the effort and quicken the process and computer resources help store large volumes of data.
Computer databases today can provide information about many species and allow new species to be added to the database. However, the database is not complete. In addition, endangered species are labeled in the database and to what known degree these species are threatened, known as the "Red List". The non-profit group IUCN helps update the database. The database is incomplete and information is continually being added.
Government legislation in many nations has been passed to help protect species from endangerment. This legislation includes international treaties, national and state laws. This legislation limits certain species from being transported across nation's borders. The Endangered Species Act in the U.S. was created in 1973 to protect endangered species and regulate hunting and fishing activities. Additional legislation has been approved to protect migratory birds in North America from hunting activities with the Migratory Bird Treaty Act (MBTA).
Private non-profit organizations also help in conservation efforts of species, such as the Nature Conservancy. The Paris Climate Agreement aims to halt or limit global temperature rise and was signed by over 194 countries, making it the largest unified world effort to reduce greenhouse gas emissions and embrace alternative energy sources to help prevent damage to ecosystems from climate change.
Conservation efforts also include establishment of wildlife and ecosystem preserves, which are specific areas of land where living species reside that are protected in some way from human activity. Scientists debate with lawmakers about how much land should be protected and to what extent. A 2003 estimate shows that 11.5 percent of Earth's land surface was covered by conservation preserves of some kind. However, these preserves do not protect all endangered species and more work is needed to determine what lands need to be preserved, or what species need to be preserved and to what degree they need to be preserved. Researchers insist that more work needs to be done at preserves to protect biodiversity.
Preserves perform better when there are buffer zones around them which allow organisms to exit the boundaries of the preserve without immediate negative consequences from predation or lack of resources. One large preserve is better than several smaller preserves because more of the habitat is unaffected by the edges. In addition, preserves with a square or circular shape are better than preserves with many thin arms for the same reason. If smaller preserves are necessary, wildlife corridors can be created between them so that individuals can move between the preserves and help connect the smaller preserves together. Wildlife corridors can be created along streams, vegetated strips, or man-made bridges. Connecting smaller preserves together allows them to behave like one larger preserve, which is beneficial to the species in the ecosystem.
Limitations of preserves for conservation efforts include political and economic pressures that usually reduce the size of preserves. In addition, establishing proper buffers around the preserve can be politically difficult. Climate change can cause species withing the preserves to migrate out of the preserve, and therefore conservationists are planning for the future effects of climate change.
A keystone species is a species that is instrumental in maintaining biodiversity in an ecosystem. Removing a keystone species from an ecological community may cause imbalance or a collapse in diversity. Examples of keystone species around the world are wolves, starfish, corals, bees, eagles, and vultures.
Recent conservation experiments involve removing aging dams from rivers and streams to restore the naturally fluctuating water levels to increase biodiversity and improved water quality.
Conservation efforts of zoos involve captive breeding programs of species and conservation education. The results of captive breeding have been mixed, but there has been some success of preserving species and preventing endangerment or extinction. In addition, there are not enough zoo facilities in the world to establish captive breeding programs for all of the species that are currently at risk. The results of the effort to educate the public about conservation of species has also been mixed as the world becomes more urbanized and humans are less connected with wildlife than in the past.