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12.2A: Human Health and Biodiversity - Biology

12.2A:  Human Health and Biodiversity - Biology


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Maintaining biodiversity ultimately helps maintain of human health; many medicines are derived from plants and, recently, animal toxins.

Learning Objectives

  • Describe the benefits to human health of maintaining biodiversity

Key Points

  • 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.
  • Antibiotics, which are responsible for extraordinary improvements in health and lifespans in developed countries, are compounds largely derived from fungi and bacteria.
  • In recent years, animal venoms and poisons have excited intense research for their medicinal potential; at least five of these drugs have been FDA approved since 2007.

Key Terms

  • atropine: an alkaloid extracted from the plant deadly nightshade (Atropa belladonna); used as a drug in medicine for its paralytic effects (in surgery to relax muscles, in dentistry to dry the mouth, etc.)
  • vincristine: a particular drug used in chemotherapy
  • antibiotic: any substance that can destroy or inhibit the growth of bacteria and similar microorganisms

Human Health

Contemporary societies that live close to the land often have a broad knowledge of the medicinal uses of plants growing in their area. Most plants produce secondary plant compounds, which are toxins used to protect the plants from insects and other animals that eat them, but some of which also work as medicines. For centuries in Europe, older knowledge about the medicinal uses of plants was compiled in herbals: books that identified plants and their uses. Humans are not the only species to use plants for medicinal reasons: the great apes (orangutans, chimpanzees, bonobos, and gorillas) have all been observed self-medicating with plants.

Modern pharmaceutical science also recognizes the importance of these plant compounds. Examples of significant medicines derived from plant compounds include aspirin, codeine, digoxin, atropine, and vincristine. Many medicines were once derived from plant extracts, but are now synthesized. It is estimated that, at one time, 25 percent of modern drugs contained at least one plant extract. That number has probably decreased to about 10 percent as natural plant ingredients are replaced by synthetic versions. Antibiotics, which are responsible for extraordinary improvements in health and lifespans in developed countries, are compounds largely derived from fungi and bacteria.

In recent years, animal venoms and poisons have excited intense research for their medicinal potential. By 2007, the FDA had approved five drugs based on animal toxins to treat diseases such as hypertension, chronic pain, and diabetes. Another five drugs are undergoing clinical trials. At least six drugs are being used in other countries. Other toxins under investigation come from mammals, snakes, lizards, various amphibians, fish, snails, octopuses, and scorpions.

Aside from representing billions of dollars in profits, these medicines improve people’s lives. Pharmaceutical companies are actively looking for new compounds synthesized by living organisms that can function as medicine. It is estimated that one-third of pharmaceutical research and development is spent on natural compounds. About 35 percent of new drugs brought to market between 1981 and 2002 were from natural compounds. The opportunities for new medications will be reduced in direct proportion to the disappearance of species. It is beneficial to humans, therefore, for medicinal purposes and many others, to maintain biodiversity.


Biodiversity and Health

Healthy communities rely on well-functioning ecosystems. They provide clean air, fresh water, medicines and food security. They also limit disease and stabilize the climate. But biodiversity loss is happening at unprecedented rates, impacting human health worldwide, according to a state of knowledge report jointly published by the Convention on Biological Diversity (CBD) and the World Health Organization (WHO).

What is biodiversity?

Biodiversity underpins all life on Earth, and refers to biological variety in all its forms, from the genetic make up of plants and animals to cultural diversity.

What does biodiversity mean for human health?

People depend on biodiversity in their daily lives, in ways that are not always apparent or appreciated. Human health ultimately depends upon ecosystem products and services (such as availability of fresh water, food and fuel sources) which are requisite for good human health and productive livelihoods. Biodiversity loss can have significant direct human health impacts if ecosystem services are no longer adequate to meet social needs. Indirectly, changes in ecosystem services affect livelihoods, income, local migration and, on occasion, may even cause or exacerbate political conflict.

Additionally, biological diversity of microorganisms, flora and fauna provides extensive benefits for biological, health, and pharmacological sciences. Significant medical and pharmacological discoveries are made through greater understanding of the earth's biodiversity. Loss in biodiversity may limit discovery of potential treatments for many diseases and health problems.

Threats to biodiversity and health

There is growing concern about the health consequences of biodiversity loss. Biodiversity changes affect ecosystem functioning and significant disruptions of ecosystems can result in life sustaining ecosystem goods and services. Biodiversity loss also means that we are losing, before discovery, many of nature's chemicals and genes, of the kind that have already provided humankind with enormous health benefits.

Nutritional impact of biodiversity

Biodiversity plays a crucial role in human nutrition through its influence on world food production, as it ensures the sustainable productivity of soils and provides the genetic resources for all crops, livestock, and marine species harvested for food. Access to a sufficiency of a nutritious variety of food is a fundamental determinant of health.

Nutrition and biodiversity are linked at many levels: the ecosystem, with food production as an ecosystem service the species in the ecosystem and the genetic diversity within species. Nutritional composition between foods and among varieties/cultivars/breeds of the same food can differ dramatically, affecting micronutrient availability in the diet. Healthy local diets, with adequate average levels of nutrients intake, necessitates maintenance of high biodiversity levels.

Intensified and enhanced food production through irrigation, use of fertilizer, plant protection (pesticides) or the introduction of crop varieties and cropping patterns affect biodiversity, and thus impact global nutritional status and human health. Habitat simplification, species loss and species succession often enhance communities vulnerabilities as a function of environmental receptivity to ill health.

Importance of biodiversity for health research and traditional medicine

Traditional medicine continue to play an essential role in health care, especially in primary health care. Traditional medicines are estimated to be used by 60% of the world&rsquos population and in some countries are extensively incorporated into the public health system. Medicinal plant use is the most common medication tool in traditional medicine and complementary medicine worldwide. Medicinal plants are supplied through collection from wild populations and cultivation. Many communities rely on natural products collected from ecosystems for medicinal and cultural purposes, in addition to food.

Although synthetic medicines are available for many purposes, the global need and demand for natural products persists for use as medicinal products and biomedical research that relies on plants, animals and microbes to understand human physiology and to understand and treat human diseases.

Infectious diseases

Human activities are disturbing both the structure and functions of ecosystems and altering native biodiversity. Such disturbances reduce the abundance of some organisms, cause population growth in others, modify the interactions among organisms, and alter the interactions between organisms and their physical and chemical environments. Patterns of infectious diseases are sensitive to these disturbances. Major processes affecting infectious disease reservoirs and transmission include, deforestation land-use change water management e.g. through dam construction, irrigation, uncontrolled urbanization or urban sprawl resistance to pesticide chemicals used to control certain disease vectors climate variability and change migration and international travel and trade and the accidental or intentional human introduction of pathogens.

Climate change, biodiversity and health

Biodiversity provides numerous ecosystem services that are crucial to human well-being at present and in the future. Climate is an integral part of ecosystem functioning and human health is impacted directly and indirectly by results of climatic conditions upon terrestrial and marine ecosystems. Marine biodiversity is affected by ocean acidification related to levels of carbon in the atmosphere. Terrestrial biodiversity is influenced by climate variability, such as extreme weather events (ie drought, flooding) that directly influence ecosystem health and the productivity and availability of ecosystem goods and services for human use. Longer term changes in climate affect the viability and health of ecosystems, influencing shifts in the distribution of plants, pathogens, animals, and even human settlements.

Key Facts

Biodiversity provides many goods and services essential to life on earth. The management of natural resources can determine the baseline health status of a community. Environmental stewardship can contribute to secure livelihoods and improve the resilience of communities. The loss of these resources can create the conditions responsible for morbidity or mortality.

Biodiversity supports human and societal needs, including food and nutrition security, energy, development of medicines and pharmaceuticals and freshwater, which together underpin good health. It also supports economic opportunities, and leisure activities that contribute to overall wellbeing.

Land use change, pollution, poor water quality, chemical and waste contamination, climate change and other causes of ecosystem degradation all contribute to biodiversity loss and, can pose considerable threats to human health.

Human health and well-being are influenced by the health of local plant and animal communities, and the integrity of the local ecosystems that they form.

Infectious diseases cause over one billion human infections per year, with millions of deaths each year globally. Approximately two thirds of known human infectious diseases are shared with animals, and the majority of recently emerging diseases are associated with wildlife.


Agricultural Diversity

Since the beginning of human agriculture more than 10,000 years ago, human groups have been breeding and selecting crop varieties. This crop diversity matched the cultural diversity of highly subdivided populations of humans. For example, potatoes were domesticated beginning around 7,000 years ago in the central Andes of Peru and Bolivia. The potatoes grown in that region belong to seven species and the number of varieties likely is in the thousands. Each variety has been bred to thrive at particular elevations and soil and climate conditions. The diversity is driven by the diverse demands of the topography, the limited movement of people, and the demands created by crop rotation for different varieties that will do well in different fields.

Potatoes are only one example of human-generated diversity. Every plant, animal, and fungus that has been cultivated by humans has been bred from original wild ancestor species into diverse varieties arising from the demands for food value, adaptation to growing conditions, and resistance to pests. The potato demonstrates a well-known example of the risks of low crop diversity: the tragic Irish potato famine when the single variety grown in Ireland became susceptible to a potato blight, wiping out the crop. The loss of the crop led to famine, death, and mass emigration. Resistance to disease is a chief benefit to maintaining crop biodiversity, and lack of diversity in contemporary crop species carries similar risks. Seed companies, which are the source of most crop varieties in developed countries, must continually breed new varieties to keep up with evolving pest organisms. These same seed companies, however, have participated in the decline of the number of varieties available as they focus on selling fewer varieties in more areas of the world.

The ability to create new crop varieties relies on the diversity of varieties available and the accessibility of wild forms related to the crop plant. These wild forms are often the source of new gene variants that can be bred with existing varieties to create varieties with new attributes. Loss of wild species related to a crop will mean the loss of potential in crop improvement. Maintaining the genetic diversity of wild species related to domesticated species ensures our continued food supply.

Since the 1920s, government agriculture departments have maintained seed banks of crop varieties as a way to maintain crop diversity. This system has flaws because, over time, seed banks are lost through accidents, and there is no way to replace them. In 2008, the Svalbard Global Seed Vault (Figure 2) began storing seeds from around the world as a backup system to the regional seed banks. If a regional seed bank stores varieties in Svalbard, losses can be replaced from Svalbard. The seed vault is located deep into the rock of an arctic island. Conditions within the vault are maintained at ideal temperature and humidity for seed survival, but the deep underground location of the vault in the arctic means that failure of the vault’s systems will not compromise the climatic conditions inside the vault.

Art Connection

Figure 2. The Svalbard Global Seed Vault is a storage facility for seeds of Earth’s diverse crops. (credit: Mari Tefre, Svalbard Global Seed Vault)

The Svalbard Global Seed Vault is located on Spitsbergen island in Norway, which has an arctic climate. Why might an arctic climate be good for seed storage?

Crop success s is largely dependent on the quality of the soil. Although some agricultural soils are rendered sterile using controversial cultivation and chemical treatments, most contain a huge diversity of organisms that maintain nutrient cycles—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. If farmers had to maintain arable soil using alternate means, the cost of food would be much higher than it is now. These kinds of processes are called ecosystem services. They occur within ecosystems, such as soil ecosystems, as a result of the diverse metabolic activities of the organisms living there, but they provide benefits to human food production, drinking water availability, and breathable air.

Other key ecosystem services related to food production are plant pollination and crop pest control. Over 150 crops in the United States require pollination to produce. One estimate of the benefit of honeybee pollination within the United States is $1.6 billion per year other pollinators contribute up to $6.7 billion more.

Many honeybee populations are managed by apiarists who rent out their hives’ services to farmers. Honeybee populations in North America have been suffering large losses caused by a syndrome known as colony collapse disorder, whose cause is unclear. Other pollinators include a diverse array of other bee species and various insects and birds. Loss of these species would make growing crops requiring pollination impossible, increasing dependence on other crops.

Finally, humans compete for their food with crop pests, most of which are insects. Pesticides control these competitors however, pesticides are costly and lose their effectiveness over time as pest populations adapt. They also lead to collateral damage by killing non-pest species and risking the health of consumers and agricultural workers. Ecologists believe that the bulk of the work in removing pests is actually done by predators and parasites of those pests, but the impact has not been well studied. A review found that in 74 percent of studies that looked for an effect of landscape complexity on natural enemies of pests, the greater the complexity, the greater the effect of pest-suppressing organisms. An experimental study found that introducing multiple enemies of pea aphids (an important alfalfa pest) increased the yield of alfalfa significantly. This study shows the importance of landscape diversity via the question of whether a diversity of pests is more effective at control than one single pest the results showed this to be the case. Loss of diversity in pest enemies will inevitably make it more difficult and costly to grow food.


Benefits of Biodiversity

Species can have instrumental or intrinsic (inherent) value. When of use to humans, either as a pleasing aspect (a pet dog) or a useful one (willow bark as a pain killer), they are instrumental. If a species has other value beyond its use to the human race, it has intrinsic value. This would include the fact that a species is part of the world’s natural history. New discussions regarding the ethics of human effects upon biodiversity sway towards agreeing that every species has intrinsic value.

Without biodiversity, ecosystems would produce less. If one species of plant type produces one type of flower for one species bee, who produces honey for one species of honey badger who provides food for one cheetah, the balance is much too delicate. If a sudden heavy downpour kills most of the bees and drowns the flowers, the entire food chain is lost. The higher the number of species that can be supported in an ecosystem, the higher the rate of survival for every organism inside that ecosystem. Including the human species.

Thanks to the planet’s huge biodiversity we have been able to produce medicines for the sick, grow new types of crops in areas which used to suffer regular famine, enjoy the colors and scents of a fantastic range of flowers, eat a varied diet with no need for deficiencies, and explore the splendor of the world’s different habitats as we travel. Biodiversity is not only necessary for survival, but it is also extremely beautiful.


National Science Foundation - Where Discoveries Begin


Wildlife biodiversity is good for human health, NSF-funded scientists have found.


April 20, 2021

A growing body of evidence suggests that biodiversity loss increases exposure to both new and established zoonotic pathogens. Restoring and protecting nature is essential to preventing future pandemics.

So reports a new Proceedings of the National Academy of Sciences paper that synthesizes current understanding about how biodiversity affects human health and provides recommendations for future research to guide management. The research is funded by the U.S. National Science Foundation.

Lead author Felicia Keesing of Bard College and the Cary Institute of Ecosystem Studies says, "There's a persistent myth that wild areas with high levels of biodiversity are hotspots for disease. More animal diversity must equal more dangerous pathogens. But that turns out to be wrong. Biodiversity isn't a threat to us it's actually protecting us from the species most likely to make us sick."

Zoonotic diseases such as COVID-19, severe acute respiratory syndrome and Ebola are caused by pathogens that are shared between humans and other vertebrate animals. But animal species differ in their ability to pass along pathogens that make humans sick.

Rick Ostfeld is a disease ecologist at the Cary Institute and a co-author of the paper. He says, "Research is mounting that species thriving in developed and degraded landscapes are often much more efficient at harboring pathogens and transmitting them to people. In less-disturbed landscapes with more animal diversity, these risky reservoirs are less abundant, and biodiversity has a protective effect."

Rodents, bats, primates, cloven-hooved mammals such as sheep and deer, and carnivores have been flagged as the mammals most likely to transmit pathogens to humans. But the next emerging pathogen is far more likely to come from a rat than a rhino, the scientists say.

Animals with short lives tend to be more efficient at transmitting pathogens. "Animals that live fast, die young, and have early sexual maturity with lots of offspring tend to invest less in their adaptive immune responses," says Keesing. "They are often better at transmitting diseases, compared to longer-lived animals with stronger adaptive immunity."

When biodiversity is lost from ecological communities, long-lived, larger-bodied species tend to disappear first, while smaller-bodied species with short lives tend to proliferate.

Human development tends to increase the abundance of zoonotic host species, bringing people and risky animals closer together, the researchers say.

Adds Diana Pilson, a program director in NSF's Division of Environmental Biology, "This important review clarifies the conditions under which zoonotic spillover is most likely to occur. The work will allow a better focus on the groups of species and environmental conditions that are likely to be sources of new zoonotic diseases."


253 The Importance of Biodiversity to Human Life

By the end of this section, you will be able to do the following:

  • Identify chemical diversity benefits to humans
  • Identify biodiversity components that support human agriculture
  • Describe ecosystem services

It may not be clear why biologists are concerned about biodiversity loss. When biodiversity loss is thought of as the extinction of the passenger pigeon, the dodo bird, and even the woolly mammoth, the loss may appear to be an emotional one. But is the loss practically important for the welfare of the human species? From the perspective of evolution and ecology, the loss of a particular individual species is unimportant (however, we should note that the loss of a keystone species can lead to ecological disaster). Extinction is a normal part of macroevolution. But the accelerated extinction rate translates into the loss of tens of thousands of species within our lifetimes, and it is likely to have dramatic effects on human welfare through the collapse of ecosystems and in added costs to maintain food production, clean air and water, and human health.

Agriculture began after early hunter-gatherer societies first settled in one place and heavily modified their immediate environment. This cultural transition has made it difficult for humans to recognize their dependence on undomesticated living things on the planet. Biologists recognize the human species is embedded in ecosystems and is dependent on them, just as every other species on the planet is dependent. Technology smooths out the extremes of existence, but ultimately the human species cannot exist without a supportive ecosystem.

Human Health

Archeological evidence indicates that humans have been using plants for medicinal uses for thousands of years. A Chinese document from approximately 2800 BC is believed to be the the first written account of herbal remedies, and such references occur throughout the global historical record. Contemporary indigenous societies that live close to the land often retain broad knowledge of the medicinal uses of plants growing in their area. 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.

Modern pharmaceutical science also recognizes the importance of these plant compounds. Examples of significant medicines derived from plant compounds include aspirin, codeine, digoxin, atropine, and vincristine ((Figure)). Many medicines were once derived from plant extracts but are now synthesized. It is estimated that, at one time, 25 percent of modern drugs contained at least one plant extract. That number has probably decreased to about 10 percent as natural plant ingredients are replaced by synthetic versions. Antibiotics, which are responsible for extraordinary improvements in health and lifespans in developed countries, are compounds largely derived from fungi and bacteria.


In recent years, animal venoms and poisons have excited intense research for their medicinal potential. By 2007, the FDA had approved five drugs based on animal toxins to treat diseases such as hypertension, chronic pain, and diabetes. Another five drugs are undergoing clinical trials, and at least six drugs are being used in other countries. Other toxins under investigation come from mammals, snakes, lizards, various amphibians, fish, snails, octopuses, and scorpions.

Aside from representing billions of dollars in profits, these medicines improve people’s lives. Pharmaceutical companies are always looking for new compounds synthesized by living organisms that can function as medicines. It is estimated that 1/3 of pharmaceutical research and development is spent on natural compounds and that about 35 percent of new drugs brought to market between 1981 and 2002 were derived from natural compounds. The opportunities for new medications will be reduced in direct proportion to the disappearance of species.

Agricultural Diversity

Since the beginning of human agriculture more than 10,000 years ago, human groups have been breeding and selecting crop varieties. This crop diversity matched the cultural diversity of highly subdivided populations of humans. For example, potatoes were domesticated beginning around 7,000 years ago in the central Andes of Peru and Bolivia. The potatoes grown in that region belong to seven species and the number of varieties likely is in the thousands. Even the Inca capital of Machu Picchu had numerous gardens growing varieties of potatoes. Each variety has been bred to thrive at particular elevations and soil and climate conditions. The diversity is driven by the diverse demands of the topography, the limited movement of people, and the demands created by crop rotation for different varieties that will do well in different fields.

Potatoes are only one example of human-generated diversity. Every plant, animal, and fungus that has been cultivated by humans has been bred from original wild ancestor species into diverse varieties arising from the demands for food value, adaptation to growing conditions, and resistance to pests.

The potato also demonstrates risks of low crop diversity. The tragic Irish potato famine occurred when the single variety grown in Ireland became susceptible to a potato blight, wiping out the entire crop. The loss of the potato crop led to mass famine and the related deaths of over one million people, as well as mass emigration of nearly two million people.

Disease resistance is a chief benefit of crop biodiversity, and lack of diversity in contemporary crop species carries similar risks. Seed companies, which are the source of most crop varieties in developed countries, must continually breed new varieties to keep up with evolving pest organisms. These same seed companies, however, have participated in the decline of the number of varieties available as they focus on selling fewer varieties in more areas of the world.

The ability to create new crop varieties relies on the diversity of varieties available and the accessibility of wild forms related to the crop plant. These wild forms are often the source of new gene variants that can be bred with existing varieties to create varieties with new attributes. Loss of wild species related to a crop will mean the loss of potential in crop improvement. Maintaining the genetic diversity of wild species related to domesticated species ensures our continued food supply.

Since the 1920s, government agriculture departments have maintained seed banks of crop varieties as a way of maintaining crop diversity. This system has flaws because, over time, seed banks are lost through accidents, and there is no way to replace them. In 2008, the Svalbard Global Seed Vault ((Figure)) began storing seeds from around the world as a backup system to the regional seed banks. If a regional seed bank stores varieties in Svalbard, losses can be replaced from Svalbard. Conditions within the vault are maintained at ideal temperature and humidity for seed survival, but the deep underground location of the vault in the arctic means that failure of the vault’s systems will not compromise the climatic conditions inside the vault.


The Svalbard Global Seed Vault is located on Spitsbergen island in Norway, which has an arctic climate. Why might an arctic climate be good for seed storage?

Crop success is largely dependent on the quality of the soil. Although some agricultural soils are rendered sterile using controversial cultivation and chemical treatments, most contain a huge diversity of organisms that maintain nutrient cycles—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. If farmers had to maintain arable soil using alternate means, the cost of food would be much higher than it is now. These kinds of processes are called ecosystem services . They occur within ecosystems, such as soil ecosystems, as a result of the diverse metabolic activities of the organisms living there, but they provide benefits to human food production, drinking water availability, and breathable air.

Plant pollination is another key ecosystem service, provided by various species of bees, other insects, and birds. One estimate indicates that honey bee pollination provides the United States a $1.6 billion annual benefit.

Honey bee populations in North America have been suffering large losses caused by a syndrome known as colony collapse disorder, whose cause is unclear. (Evidence suggests the possible culprits may be the invasive varroa mite coupled with the Nosema gut parasite and acute paralysis virus.) Loss of these species would render it very difficult, if not impossible, to grow any of the 150 United States crops requiring pollination, including grapes, oranges, lemons, peppers, most brassica (broccoli and cauliflower), and many berries, melons, and nuts.

Finally, humans compete for their food with crop pests, most of which are insects. Pesticides control these competitors however, pesticides are costly and lose their effectiveness over time as pest populations adapt and evolve. They also lead to collateral damage by killing non-pest species and risking the health of consumers and agricultural workers. Ecologists believe that the bulk of the work in removing pests is actually done by predators and parasites of those pests, but the impact has not been well studied. A review found that in 74 percent of studies that looked for an effect of landscape complexity on natural enemies of pests, the greater the complexity, the greater the effect of pest-suppressing organisms. An experimental study found that introducing multiple enemies of pea aphids (an important alfalfa pest) increased the yield of alfalfa significantly. This study shows the importance of landscape diversity via the question of whether a diversity of pests is more effective at control than one single pest the results showed this to be the case. Loss of diversity in pest enemies will inevitably make it more difficult and costly to grow food.

Wild Food Sources

In addition to growing crops and raising animals for food, humans obtain food resources from wild populations, primarily fish populations. In fact, for approximately 1 billion people worldwide, aquatic resources provide the main source of animal protein. But since 1990, global fish production has declined, sometimes dramatically. Unfortunately, and despite considerable effort, few fisheries on the planet are managed for sustainability.

Fishery extinctions rarely lead to complete extinction of the harvested species, but rather to a radical restructuring of the marine ecosystem in which a dominant species is so over-harvested that it becomes a minor player, ecologically. In addition to humans losing the food source, these alterations affect many other species in ways that are difficult or impossible to predict. The collapse of fisheries has dramatic and long-lasting effects on local populations that work in the fishery. In addition, the loss of an inexpensive protein source to populations that cannot afford to replace it will increase the cost of living and limit societies in other ways. In general, the fish taken from fisheries have shifted to smaller species as larger species are fished to extinction. The ultimate outcome could clearly be the loss of aquatic systems as food sources.

View a brief video discussing declining fish stocks.

Psychological and Moral Value

Finally, it has been clearly shown that humans benefit psychologically from living in a biodiverse world. A chief proponent of this idea is Harvard entomologist E. O. Wilson. He argues that human evolutionary history has adapted us to live in a natural environment and that city environments generate psychological stressors that affect human health and well-being. There is considerable research into the psychological regenerative benefits of natural landscapes that suggests the hypothesis may hold some truth. In addition, there is a moral argument that humans have a responsibility to inflict as little harm as possible on other species.

Section Summary

Humans use many compounds that were first discovered or derived from living organisms as medicines: secondary plant compounds, animal toxins, and antibiotics produced by bacteria and fungi. More medicines will undoubtedly be discovered in nature. Loss of biodiversity will impact the number of pharmaceuticals available to humans.

Crop diversity is a requirement for food security, and it is being lost. The loss of wild relatives to crops also threatens breeders’ abilities to create new varieties. Ecosystems provide ecosystem services that support human agriculture: pollination, nutrient cycling, pest control, and soil development and maintenance. Loss of biodiversity threatens these ecosystem services and risks making food production more expensive or impossible. Wild food sources are mainly aquatic, but few of these resources are being managed for sustainability. Fisheries’ ability to provide protein to human populations is threatened when extinction occurs.

Biodiversity may provide important psychological benefits to humans. Additionally, there are moral arguments for the maintenance of biodiversity.

Visual Connection Questions

(Figure) The Svalbard Global Seed Vault is located on Spitsbergen island in Norway, which has an arctic climate. Why might an arctic climate be good for seed storage?

(Figure) The ground is permanently frozen so the seeds will keep even if the electricity fails.

Review Questions

A secondary plant compound might be used for which of the following?

  1. a new crop variety
  2. a new drug
  3. a soil nutrient
  4. a pest of a crop pest

Pollination is an example of ________.

  1. a possible source of new drugs
  2. chemical diversity
  3. an ecosystem service
  4. crop pest control

What is an ecosystem service that performs the same function as a pesticide?

  1. pollination
  2. secondary plant compounds
  3. crop diversity
  4. predators of pests

Critical Thinking Questions

Explain how biodiversity loss can impact crop diversity.

Crop plants are derived from wild plants, and genes from wild relatives are frequently brought into crop varieties by plant breeders to add valued characteristics to the crops. If the wild species are lost, then this genetic variation would no longer be available.

Describe two types of compounds from living things that are used as medications.

Secondary plant compounds are toxins produced by plants to kill predators trying to eat them some of these compounds can be used as drugs. Animal toxins such as snake venom can also be used as drugs. (Alternate answer: antibiotics are compounds produced by bacteria and fungi which can be used to kill bacteria.)

Glossary


Human Health

Contemporary societies that live close to the land often have a broad knowledge of the medicinal uses of plants growing in their area. 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. For centuries in Europe, older knowledge about the medical uses of plants was compiled in herbals—books that identified plants and their uses. Humans are not the only species to use plants for medicinal reasons: the great apes, orangutans, chimpanzees, bonobos, and gorillas have all been observed self-medicating with plants.

Modern pharmaceutical science also recognizes the importance of these plant compounds. Examples of significant medicines derived from plant compounds include aspirin, codeine, digoxin, atropine, and vincristine (see the figure below). Many medicines were once derived from plant extracts but are now synthesized. It is estimated that, at one time, 25 percent of modern drugs contained at least one plant extract. That number has probably decreased to about 10 percent as natural plant ingredients are replaced by synthetic versions. Antibiotics, which are responsible for extraordinary improvements in health and lifespans in developed countries, are compounds largely derived from fungi and bacteria.

Catharanthus roseus, the Madagascar periwinkle, has various medicinal properties. Among other uses, it is a source of vincristine, a drug used in the treatment of lymphomas. (credit: Forest and Kim Starr)

In recent years, animal venoms and poisons have excited intense research for their medicinal potential. By 2007, the FDA had approved five drugs based on animal toxins to treat diseases such as hypertension, chronic pain, and diabetes. Another five drugs are undergoing clinical trials, and at least six drugs are being used in other countries. Other toxins under investigation come from mammals, snakes, lizards, various amphibians, fish, snails, octopuses, and scorpions.

Aside from representing billions of dollars in profits, these medicines improve people’s lives. Pharmaceutical companies are actively looking for new compounds synthesized by living organisms that can function as medicine. It is estimated that 1/3 of pharmaceutical research and development is spent on natural compounds and that about 35 percent of new drugs brought to market between 1981 and 2002 were from natural compounds. The opportunities for new medications will be reduced in direct proportion to the disappearance of species.


Biodiversity devastation: Human-driven decline requires millions of years of recovery

Lake Volvi (Greece) temporarily dries up as a consequence of excessive irrigation for agriculture paired with climate change - one of many examples of a freshwater system under human impact. Credit: C. Albrecht (JLU)

A new study shows that the current rate of biodiversity decline in freshwater ecosystems outcompetes that at the end-Cretaceous extinction that killed the dinosaurs: damage now being done in decades to centuries may take millions of years to undo.

The current biodiversity crisis, often called the 6th mass extinction, is one of the critical challenges we face in the 21st century. Numerous species are threatened with extinction, mostly as a direct or indirect consequence of human impact. Habitat destruction, climate change, overexploitation, pollution and invasive species are among the main causes for Earth's biota to decline rapidly.

To investigate the tempo of extinction and predict recovery times, an international team of evolutionary biologists, paleontologists, geologists and modelers led by the Justus Liebig University Giessen compared today's crisis with the previous, 5th mass extinction event. That event was the result of an asteroid impact 66 million years ago, eradicating about 76% of all species on the planet, including entire animal groups such as the dinosaurs. Focusing on freshwater biota, which are among the World's most threatened, the research team gathered a large dataset containing 3,387 fossil and living snail species of Europe covering the past 200 million years. The scientists estimated rates of speciation and extinction to assess the speed at which species come and go and predict recovery times.

Microcolpia parreyssii (Philippi, 1847), a freshwater snail from a small thermal spring in Romania. The species is flagged as "critically endangered" by the IUCN Red List, but it has not been found living in the past few years and is probably extinct in the wild. Credit: Thomas A. Neubauer

The results of the study, which are recently published in the journal Communications Earth & Environment, are alarming. While already the extinction rate during the 5th mass extinction was considerably higher than previously believed for freshwater biota, it is drastically overshadowed by the predicted future extinction rate of the current 6th mass extinction event. On average the predicted rate was three orders of magnitudes higher than during the time the dinosaurs went extinct. Already by 2120 a third of the living freshwater species may have vanished.

Pyrgulifera matheronii, a freshwater snail common at the time of the dinosaurs and extinct along with them. Cretaceous, Hungary. Credit: Mathias Harzhauser, NHM Vienna.

The pace at which we lose species today is unprecedented and has not even been reached during major extinction crises in the past. "Losing species entails changes in species communities and, in the long run, this affects entire ecosystems. We rely on functioning freshwater environments to sustain human health, nutrition and fresh water supply," says the lead author of the study, Dr. Thomas A. Neubauer.

The trend the scientists revealed for the fifth mass extinction event has another, potentially even more dire prospect for the future. Although the cause for the rising extinction—an asteroid impact on the Yucatán Peninsula in Mexico—was a short event in geological time scales, the extinction rate remained high for approximately five million years. Afterwards followed an even longer period of recovery. It took altogether nearly 12 million years until the balance was restored between species originating and going extinct.

"Even if our impact on the world's biota stops today, the extinction rate will likely stay high for an extended period of time. Considering that the current biodiversity crisis advances much faster than the mass extinction event 66 million years ago, the recovery period may be even longer," says Neubauer. "Despite our short existence on Earth, we have assured that the effects of our actions will outlast us by millions of years."


Human health and biodiversity are interrelated

According to a new report, presented at the 14th World Congress on Public Health held in India, human health and biodiversity are intimately connected.

According to the innovative Connecting Global Priorities: Biodiversity and Human Health report, presented last February at the 14th World Congress on Public Health, held in Kolkata, India, protecting animals, plants and ecosystems means protecting our health.

The report was published by the Secretariat of the Convention on Biological Diversity (SCBD) and the World Health Organization (WHO), in cooperation with several associations. The interrelation between human health and biological diversity is considerable and complex and the current biodiversity loss, taking place at unprecedented rates, is altering a delicate balance.

The report explains how biodiversity and human health are intimately interrelated and have a mutual impact, for instance, on water and air quality, food production, diet, microbial diversity and non-transmissible diseases.

Biodiversity is a source of food, nutrients, medicines, fuel, energy, livelihoods and cultural and spiritual enrichment. It contributes to the provision of clean water and air, and perform critical functions that range from the regulation of pests and disease to that of climate change and natural disasters,” stated Braulio Ferreira de Souza Dias, Executive Secretary of the Convention on Biological Diversity.

According to experts, climate change will have a serious impact on human health and will deteriorate farming systems and reduce nutrients in some foods. In this case, biodiversity increase resilience, or else ecosystems recovery capacity, thus helping adjustment to new environmental conditions.

Coral reefs safeguard, for instance, is essential to reduce the risk of floods, as this extraordinary ecosystem can reduce wave energy by 97%, thus protecting over 1o0 million people all over the world.

The report also stresses the importance of sustainable consumption and production, and hope for a more widespread use of contraceptives to reduce the constant growth of the world population, which figures among the major threats to human health and biodiversity.

The report also stresses the importance of sustainable consumption and production, and hope for a more widespread use of contraceptives to reduce the constant growth of the world population, which figures among the major threats to human health and biodiversity.


Watch the video: Biotechnology and its Applications - All Theory, Tricks u0026 Main lines Underline. Target NEET 2021 (May 2022).


Comments:

  1. Spangler

    Between us say, try searching for the answer to your question in google.com

  2. Hudak

    Bravo, what words ..., a great idea

  3. Visida

    Perhaps



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