🤩 Discover new information from across the web

Biodiversity

Degree of variation of life forms

Top 10 Biodiversity related articles

A sampling of fungi collected during summer 2008 in Northern Saskatchewan mixed woods, near LaRonge, is an example regarding the species diversity of fungi. In this photo, there are also leaf lichens and mosses.

Biodiversity is the biological variety and variability of life on Earth. Biodiversity is typically a measure of variation at the genetic, species, and ecosystem level.[1] Terrestrial biodiversity is usually greater near the equator,[2] which is the result of the warm climate and high primary productivity.[3] Biodiversity is not distributed evenly on Earth, and is richer in the tropics.[4] These tropical forest ecosystems cover less than 10 percent of earth's surface, and contain about 90 percent of the world's species.[5] Marine biodiversity is usually higher along coasts in the Western Pacific, where sea surface temperature is highest, and in the mid-latitudinal band in all oceans.[6] There are latitudinal gradients in species diversity.[6] Biodiversity generally tends to cluster in hotspots,[7] and has been increasing through time,[8][9] but will be likely to slow in the future as a primary result of deforestation.[10]

Rapid environmental changes typically cause mass extinctions.[11][12][13] More than 99.9 percent of all species that ever lived on Earth, amounting to over five billion species,[14] are estimated to be extinct.[15][16] Estimates on the number of Earth's current species range from 10 million to 14 million,[17] of which about 1.2 million have been documented and over 86 percent have not yet been described.[18] More recently, in May 2016, scientists reported that 1 trillion species are estimated to be on Earth currently with only one-thousandth of one percent described.[19] The total amount of related DNA base pairs on Earth is estimated at 5.0 x 1037 and weighs 50 billion tonnes.[20] In comparison, the total mass of the biosphere has been estimated to be as much as 4 TtC (trillion tons of carbon).[21] In July 2016, scientists reported identifying a set of 355 genes from the Last Universal Common Ancestor (LUCA) of all organisms living on Earth.[22]

The age of the Earth is about 4.54 billion years.[23][24][25] The earliest undisputed evidence of life on Earth dates at least from 3.5 billion years ago,[26][27][28] during the Eoarchean Era after a geological crust started to solidify following the earlier molten Hadean Eon. There are microbial mat fossils found in 3.48 billion-year-old sandstone discovered in Western Australia.[29][30][31] Other early physical evidence of a biogenic substance is graphite in 3.7 billion-year-old meta-sedimentary rocks discovered in Western Greenland.[32] More recently, in 2015, "remains of biotic life" were found in 4.1 billion-year-old rocks in Western Australia.[33][34] According to one of the researchers, "If life arose relatively quickly on Earth .. then it could be common in the universe."[33]

Since life began on Earth, five major mass extinctions and several minor events have led to large and sudden drops in biodiversity. The Phanerozoic eon (the last 540 million years) marked a rapid growth in biodiversity via the Cambrian explosion—a period during which the majority of multicellular phyla first appeared.[35] The next 400 million years included repeated, massive biodiversity losses classified as mass extinction events. In the Carboniferous, rainforest collapse led to a great loss of plant and animal life.[36] The Permian–Triassic extinction event, 251 million years ago, was the worst; vertebrate recovery took 30 million years.[37] The most recent, the Cretaceous–Paleogene extinction event, occurred 65 million years ago and has often attracted more attention than others because it resulted in the extinction of the non-avian dinosaurs.[38]

The period since the emergence of humans has displayed an ongoing biodiversity reduction and an accompanying loss of genetic diversity. Named the Holocene extinction, the reduction is caused primarily by human impacts, particularly habitat destruction.[39] Conversely, biodiversity positively impacts human health in a number of ways, although a few negative effects are studied.[40]

The United Nations designated 2011–2020 as the United Nations Decade on Biodiversity.[41] and 2021–2030 as the United Nations Decade on Ecosystem Restoration[42] According to a 2019 Global Assessment Report on Biodiversity and Ecosystem Services by IPBES, 25% of plant and animal species are threatened with extinction as the result of human activity.[43][44][45] An October 2020 IPBES report found the same human actions which drive biodiversity loss have also resulted in an increase in pandemics.[46]

In 2020, the fifth edition of the UN's Global Biodiversity Outlook report,[47] which served as a “final report card” for the Aichi Biodiversity Targets, a series of 20 objectives set out in 2010, at the beginning of the UN's Decade on Biodiversity, most of which were supposed to be reached by the end of the year 2020, stated that none of the targets – which concern the safeguarding of ecosystems, and the promotion of sustainability – have been fully met.[48]

Biodiversity Intro articles: 55

History of terminology

  • 1916 – The term biological diversity was used first by J. Arthur Harris in "The Variable Desert," Scientific American, JSTOR 6182: "The bare statement that the region contains a flora rich in genera and species and of diverse geographic origin or affinity is entirely inadequate as a description of its real biological diversity."
  • 1974 – The term natural diversity was introduced by John Terborgh ("The Preservation of Natural Diversity: The Problem of Extinction Prone Species," BioScience 24 (12): 715–722. https://doi.org/10.2307/1297090).
  • 1980 – Thomas Lovejoy introduced the term biological diversity to the scientific community in a book.[49] It rapidly became commonly used.[50]
  • 1985 – According to Edward O. Wilson, the contracted form biodiversity was coined by W. G. Rosen: "The National Forum on BioDiversity ... was conceived by Walter G.Rosen ... Dr. Rosen represented the NRC/NAS throughout the planning stages of the project. Furthermore, he introduced the term biodiversity".[51]
  • 1985 - The term "biodiversity" appears in the article, "A New Plan to Conserve the Earth's Biota" by Laura Tangley.[52]
  • 1988 - The term biodiversity first appeared in a publication.[53][54]
  • The present - the term has achieved widespread use.

Definitions

Prior term

"Biodiversity" is most commonly used to replace the more clearly defined and long established terms, species diversity and species richness.[55]

Alternate terms

Biologists most often define biodiversity as the "totality of genes, species and ecosystems of a region".[56][57] An advantage of this definition is that it seems to describe most circumstances and presents a unified view of the traditional types of biological variety previously identified:

Wilcox 1982

An explicit definition consistent with this interpretation was first given in a paper by Bruce A. Wilcox commissioned by the International Union for the Conservation of Nature and Natural Resources (IUCN) for the 1982 World National Parks Conference.[61] Wilcox's definition was "Biological diversity is the variety of life forms...at all levels of biological systems (i.e., molecular, organismic, population, species and ecosystem)...".[61]

Genetic: Wilcox 1984

Biodiversity can be defined genetically as the diversity of alleles, genes and organisms. They study processes such as mutation and gene transfer that drive evolution.[61]

United Nations 1992

The 1992 United Nations Earth Summit defined "biological diversity" as "the variability among living organisms from all sources, including, inter alia, terrestrial, marine and other aquatic ecosystems and the ecological complexes of which they are part: this includes diversity within species, between species and of ecosystems".[62] This definition is used in the United Nations Convention on Biological Diversity.[62]

Gaston and Spicer 2004

Gaston & Spicer's definition in their book "Biodiversity: an introduction" is "variation of life at all levels of biological organization".[63]

Food and Agriculture Organization 2020

What is forest biological biodiversity?

Forest biological diversity is a broad term that refers to all life forms found within forested areas and the ecological roles they perform. As such, forest biological diversity encompasses not just trees, but the multitude of plants, animals and microorganisms that inhabit forest areas and their associated genetic diversity. Forest biological diversity can be considered at different levels, including ecosystem, landscape, species, population and genetic. Complex interactions can occur within and between these levels. In biologically diverse forests, this complexity allows organisms to adapt to continually changing environmental conditions and to maintain ecosystem functions.

In the annex to Decision II/9 (CBD, n.d.a), the Conference of the Parties to the CBD recognized that: “Forest biological diversity results from evolutionary processes over thousands and even millions of years which, in themselves, are driven by ecological forces such as climate, fire, competition and disturbance. Furthermore, the diversity of forest ecosystems (in both physical and biological features) results in high levels of adaptation, a feature of forest ecosystems which is an integral component of their biological diversity. Within specific forest ecosystems, the maintenance of ecological processes is dependent upon the maintenance of their biological diversity.”[64]

Biodiversity History of terminology articles: 15

Distribution

Distribution of living terrestrial vertebrate species, highest concentration of diversity shown in red in equatorial regions, declining polewards (towards the blue end of the spectrum) (Mannion 2014)

Biodiversity is not evenly distributed, rather it varies greatly across the globe as well as within regions. Among other factors, the diversity of all living things (biota) depends on temperature, precipitation, altitude, soils, geography and the presence of other species. The study of the spatial distribution of organisms, species and ecosystems, is the science of biogeography.[65][66]

Diversity consistently measures higher in the tropics and in other localized regions such as the Cape Floristic Region and lower in polar regions generally. Rain forests that have had wet climates for a long time, such as Yasuní National Park in Ecuador, have particularly high biodiversity.[67][68]

Terrestrial biodiversity is thought to be up to 25 times greater than ocean biodiversity.[69] Forests harbour most of Earth's terrestrial biodiversity. The conservation of the world's biodiversity is thus utterly dependent on the way in which we interact with and use the world's forests.[70] A new method used in 2011, put the total number of species on Earth at 8.7 million, of which 2.1 million were estimated to live in the ocean.[71] However, this estimate seems to under-represent the diversity of microorganisms.[72] Forests provide habitats for 80 percent of amphibian species, 75 percent of bird species and 68 percent of mammal species. About 60 percent of all vascular plants are found in tropical forests. Mangroves provide breeding grounds and nurseries for numerous species of fish and shellfish and help trap sediments that might otherwise adversely affect seagrass beds and coral reefs, which are habitats for many more marine species.[73]

The biodiversity of forests varies considerably according to factors such as forest type, geography, climate and soils – in addition to human use.[74] Most forest habitats in temperate regions support relatively few animal and plant species and species that tend to have large geographical distributions, while the montane forests of Africa, South America and Southeast Asia and lowland forests of Australia, coastal Brazil, the Caribbean islands, Central America and insular Southeast Asia have many species with small geographical distributions.[74] Areas with dense human populations and intense agricultural land use, such as Europe, parts of Bangladesh, China, India and North America, are less intact in terms of their biodiversity. Northern Africa, southern Australia, coastal Brazil, Madagascar and South Africa, are also identified as areas with striking losses in biodiversity intactness.[74]

Latitudinal gradients

Generally, there is an increase in biodiversity from the poles to the tropics. Thus localities at lower latitudes have more species than localities at higher latitudes. This is often referred to as the latitudinal gradient in species diversity. Several ecological factors may contribute to the gradient, but the ultimate factor behind many of them is the greater mean temperature at the equator compared to that of the poles.[75][76][77]

Even though terrestrial biodiversity declines from the equator to the poles,[78] some studies claim that this characteristic is unverified in aquatic ecosystems, especially in marine ecosystems.[79] The latitudinal distribution of parasites does not appear to follow this rule.[65]

In 2016, an alternative hypothesis ("the fractal biodiversity") was proposed to explain the biodiversity latitudinal gradient.[80] In this study, the species pool size and the fractal nature of ecosystems were combined to clarify some general patterns of this gradient. This hypothesis considers temperature, moisture, and net primary production (NPP) as the main variables of an ecosystem niche and as the axis of the ecological hypervolume. In this way, it is possible to build fractal hyper volumes, whose fractal dimension rises to three moving towards the equator.[81]

Biodiversity Hotspot

A biodiversity hotspot is a region with a high level of endemic species that have experienced great habitat loss.[82] The term hotspot was introduced in 1988 by Norman Myers.[83][84][85][86] While hotspots are spread all over the world, the majority are forest areas and most are located in the tropics.

Brazil's Atlantic Forest is considered one such hotspot, containing roughly 20,000 plant species, 1,350 vertebrates and millions of insects, about half of which occur nowhere else.[87] The island of Madagascar and India are also particularly notable. Colombia is characterized by high biodiversity, with the highest rate of species by area unit worldwide and it has the largest number of endemics (species that are not found naturally anywhere else) of any country. About 10% of the species of the Earth can be found in Colombia, including over 1,900 species of bird, more than in Europe and North America combined, Colombia has 10% of the world's mammals species, 14% of the amphibian species and 18% of the bird species of the world.[88] Madagascar dry deciduous forests and lowland rainforests possess a high ratio of endemism.[89][90] Since the island separated from mainland Africa 66 million years ago, many species and ecosystems have evolved independently.[91] Indonesia's 17,000 islands cover 735,355 square miles (1,904,560 km2) and contain 10% of the world's flowering plants, 12% of mammals and 17% of reptiles, amphibians and birds—along with nearly 240 million people.[92] Many regions of high biodiversity and/or endemism arise from specialized habitats which require unusual adaptations, for example, alpine environments in high mountains, or Northern European peat bogs.[90]

Accurately measuring differences in biodiversity can be difficult. Selection bias amongst researchers may contribute to biased empirical research for modern estimates of biodiversity. In 1768, Rev. Gilbert White succinctly observed of his Selborne, Hampshire "all nature is so full, that that district produces the most variety which is the most examined."[93]

Biodiversity Distribution articles: 45

Evolution

Apparent marine fossil diversity during the Phanerozoic[94]

Chronology

Biodiversity is the result of 3.5 billion years of evolution.[12] The origin of life has not been established by science, however, some evidence suggests that life may already have been well-established only a few hundred million years after the formation of the Earth. Until approximately 2.5 billion years ago, all life consisted of microorganismsarchaea, bacteria, and single-celled protozoans and protists.[72]

The history of biodiversity during the Phanerozoic (the last 540 million years), starts with rapid growth during the Cambrian explosion—a period during which nearly every phylum of multicellular organisms first appeared.[95] Over the next 400 million years or so, invertebrate diversity showed little overall trend and vertebrate diversity shows an overall exponential trend.[58] This dramatic rise in diversity was marked by periodic, massive losses of diversity classified as mass extinction events.[58] A significant loss occurred when rainforests collapsed in the carboniferous.[36] The worst was the Permian-Triassic extinction event, 251 million years ago. Vertebrates took 30 million years to recover from this event.[37]

The fossil record suggests that the last few million years featured the greatest biodiversity in history.[58] However, not all scientists support this view, since there is uncertainty as to how strongly the fossil record is biased by the greater availability and preservation of recent geologic sections.[26] Some scientists believe that corrected for sampling artifacts, modern biodiversity may not be much different from biodiversity 300 million years ago,[95] whereas others consider the fossil record reasonably reflective of the diversification of life.[58] Estimates of the present global macroscopic species diversity vary from 2 million to 100 million, with a best estimate of somewhere near 9 million,[71] the vast majority arthropods.[96] Diversity appears to increase continually in the absence of natural selection.[97]

Diversification

The existence of a global carrying capacity, limiting the amount of life that can live at once, is debated, as is the question of whether such a limit would also cap the number of species. While records of life in the sea show a logistic pattern of growth, life on land (insects, plants and tetrapods) shows an exponential rise in diversity.[58] As one author states, "Tetrapods have not yet invaded 64 percent of potentially habitable modes and it could be that without human influence the ecological and taxonomic diversity of tetrapods would continue to increase exponentially until most or all of the available eco-space is filled."[58]

It also appears that the diversity continues to increase over time, especially after mass extinctions.[98]

On the other hand, changes through the Phanerozoic correlate much better with the hyperbolic model (widely used in population biology, demography and macrosociology, as well as fossil biodiversity) than with exponential and logistic models. The latter models imply that changes in diversity are guided by a first-order positive feedback (more ancestors, more descendants) and/or a negative feedback arising from resource limitation. Hyperbolic model implies a second-order positive feedback.[99] Differences in the strength of the second-order feedback due to different intensities of interspecific competition might explain the faster rediversification of ammonoids in comparison to bivalves after the end-Permian extinction.[99] The hyperbolic pattern of the world population growth arises from a second-order positive feedback between the population size and the rate of technological growth.[100] The hyperbolic character of biodiversity growth can be similarly accounted for by a feedback between diversity and community structure complexity.[100][101] The similarity between the curves of biodiversity and human population probably comes from the fact that both are derived from the interference of the hyperbolic trend with cyclical and stochastic dynamics.[100][101]

Most biologists agree however that the period since human emergence is part of a new mass extinction, named the Holocene extinction event, caused primarily by the impact humans are having on the environment.[102] It has been argued that the present rate of extinction is sufficient to eliminate most species on the planet Earth within 100 years.[103]

New species are regularly discovered (on average between 5–10,000 new species each year, most of them insects) and many, though discovered, are not yet classified (estimates are that nearly 90% of all arthropods are not yet classified).[96] Most of the terrestrial diversity is found in tropical forests and in general, the land has more species than the ocean; some 8.7 million species may exist on Earth, of which some 2.1 million live in the ocean.[71]

Biodiversity Evolution articles: 34

Ecosystem services

Summer field in Belgium (Hamois). The blue flowers are Centaurea cyanus and the red are Papaver rhoeas.

The balance of evidence

"Ecosystem services are the suite of benefits that ecosystems provide to humanity."[104] The natural species, or biota, are the caretakers of all ecosystems. It is as if the natural world is an enormous bank account of capital assets capable of paying life sustaining dividends indefinitely, but only if the capital is maintained.[105]

These services come in three flavors:

  1. Provisioning services which involve the production of renewable resources (e.g.: food, wood, fresh water)[104]
  2. Regulating services which are those that lessen environmental change (e.g.: climate regulation, pest/disease control)[104]
  3. Cultural services represent human value and enjoyment (e.g.: landscape aesthetics, cultural heritage, outdoor recreation and spiritual significance)[106]

There have been many claims about biodiversity's effect on these ecosystem services, especially provisioning and regulating services.[104] After an exhaustive survey through peer-reviewed literature to evaluate 36 different claims about biodiversity's effect on ecosystem services, 14 of those claims have been validated, 6 demonstrate mixed support or are unsupported, 3 are incorrect and 13 lack enough evidence to draw definitive conclusions.[104]

Services enhanced

Provisioning services

Greater species diversity

  • of plants increases fodder yield (synthesis of 271 experimental studies).[66]
  • of plants (i.e. diversity within a single species) increases overall crop yield (synthesis of 575 experimental studies).[107] Although another review of 100 experimental studies reports mixed evidence.[108]
  • of trees increases overall wood production (Synthesis of 53 experimental studies).[109] However, there is not enough data to draw a conclusion about the effect of tree trait diversity on wood production.[104]
Regulating services

Greater species diversity

  • of fish increases the stability of fisheries yield (Synthesis of 8 observational studies)[104]
  • of natural pest enemies decreases herbivorous pest populations (Data from two separate reviews; Synthesis of 266 experimental and observational studies;[110] Synthesis of 18 observational studies.[111][112] Although another review of 38 experimental studies found mixed support for this claim, suggesting that in cases where mutual intraguild predation occurs, a single predatory species is often more effective[113]
  • of plants decreases disease prevalence on plants (Synthesis of 107 experimental studies)[114]
  • of plants increases resistance to plant invasion (Data from two separate reviews; Synthesis of 105 experimental studies;[114] Synthesis of 15 experimental studies[115])
  • of plants increases carbon sequestration, but note that this finding only relates to actual uptake of carbon dioxide and not long-term storage, see below; Synthesis of 479 experimental studies)[66]
  • plants increases soil nutrient remineralization (Synthesis of 103 experimental studies)[114]
  • of plants increases soil organic matter (Synthesis of 85 experimental studies)[114]

Services with mixed evidence

Provisioning services
  • None to date
Regulating services
  • Greater species diversity of plants may or may not decrease herbivorous pest populations. Data from two separate reviews suggest that greater diversity decreases pest populations (Synthesis of 40 observational studies;[116] Synthesis of 100 experimental studies).[108] One review found mixed evidence (Synthesis of 287 experimental studies[117]), while another found contrary evidence (Synthesis of 100 experimental studies[114])
  • Greater species diversity of animals may or may not decrease disease prevalence on those animals (Synthesis of 45 experimental and observational studies),[118] although a 2013 study offers more support showing that biodiversity may in fact enhance disease resistance within animal communities, at least in amphibian frog ponds.[119] Many more studies must be published in support of diversity to sway the balance of evidence will be such that we can draw a general rule on this service.
  • Greater species and trait diversity of plants may or may not increase long term carbon storage (Synthesis of 33 observational studies)[104]
  • Greater pollinator diversity may or may not increase pollination (Synthesis of 7 observational studies),[104] but a publication from March 2013 suggests that increased native pollinator diversity enhances pollen deposition (although not necessarily fruit set as the authors would have you believe, for details explore their lengthy supplementary material).[120]

Services hindered

Provisioning services
  • Greater species diversity of plants reduces primary production (Synthesis of 7 experimental studies)[66]
Regulating services
  • greater genetic and species diversity of a number of organisms reduces freshwater purification (Synthesis of 8 experimental studies, although an attempt by the authors to investigate the effect of detritivore diversity on freshwater purification was unsuccessful due to a lack of available evidence (only 1 observational study was found[104]
Provisioning services
  • Effect of species diversity of plants on biofuel yield (In a survey of the literature, the investigators only found 3 studies)[104]
  • Effect of species diversity of fish on fishery yield (In a survey of the literature, the investigators only found 4 experimental studies and 1 observational study)[104]
Regulating services
  • Effect of species diversity on the stability of biofuel yield (In a survey of the literature, the investigators did not find any studies)[104]
  • Effect of species diversity of plants on the stability of fodder yield (In a survey of the literature, the investigators only found 2 studies)[104]
  • Effect of species diversity of plants on the stability of crop yield (In a survey of the literature, the investigators only found 1 study)[104]
  • Effect of genetic diversity of plants on the stability of crop yield (In a survey of the literature, the investigators only found 2 studies)[104]
  • Effect of diversity on the stability of wood production (In a survey of the literature, the investigators could not find any studies)[104]
  • Effect of species diversity of multiple taxa on erosion control (In a survey of the literature, the investigators could not find any studies – they did, however, find studies on the effect of species diversity and root biomass)[104]
  • Effect of diversity on flood regulation (In a survey of the literature, the investigators could not find any studies)[104]
  • Effect of species and trait diversity of plants on soil moisture (In a survey of the literature, the investigators only found 2 studies)[104]

Other sources have reported somewhat conflicting results and in 1997 Robert Costanza and his colleagues reported the estimated global value of ecosystem services (not captured in traditional markets) at an average of $33 trillion annually.[121]

Since the Stone Age, species loss has accelerated above the average basal rate, driven by human activity. Estimates of species losses are at a rate 100–10,000 times as fast as is typical in the fossil record.[122] Biodiversity also affords many non-material benefits including spiritual and aesthetic values, knowledge systems and education.[122]

Agriculture

Agricultural diversity can be divided into two categories: intraspecific diversity, which includes the genetic variation within a single species, like the potato (Solanum tuberosum) that is composed of many different forms and types (e.g. in the U.S. they might compare russet potatoes with new potatoes or purple potatoes, all different, but all part of the same species, S. tuberosum).

The other category of agricultural diversity is called interspecific diversity and refers to the number and types of different species. Thinking about this diversity we might note that many small vegetable farmers grow many different crops like potatoes and also carrots, peppers, lettuce, etc.

Agricultural diversity can also be divided by whether it is 'planned' diversity or 'associated' diversity. This is a functional classification that we impose and not an intrinsic feature of life or diversity. Planned diversity includes the crops which a farmer has encouraged, planted or raised (e.g. crops, covers, symbionts, and livestock, among others), which can be contrasted with the associated diversity that arrives among the crops, uninvited (e.g. herbivores, weed species and pathogens, among others).[123]

The control of associated biodiversity is one of the great agricultural challenges that farmers face. On monoculture farms, the approach is generally to eradicate associated diversity using a suite of biologically destructive pesticides, mechanized tools and transgenic engineering techniques, then to rotate crops. Although some polyculture farmers use the same techniques, they also employ integrated pest management strategies as well as more labor-intensive strategies, but generally less dependent on capital, biotechnology, and energy.

Interspecific crop diversity is, in part, responsible for offering variety in what we eat. Intraspecific diversity, the variety of alleles within a single species, also offers us a choice in our diets. If a crop fails in a monoculture, we rely on agricultural diversity to replant the land with something new. If a wheat crop is destroyed by a pest we may plant a hardier variety of wheat the next year, relying on intraspecific diversity. We may forgo wheat production in that area and plant a different species altogether, relying on interspecific diversity. Even an agricultural society that primarily grows monocultures relies on biodiversity at some point.

  • The Irish potato blight of 1846 was a major factor in the deaths of one million people and the emigration of about two million. It was the result of planting only two potato varieties, both vulnerable to the blight, Phytophthora infestans, which arrived in 1845[123]
  • When rice grassy stunt virus struck rice fields from Indonesia to India in the 1970s, 6,273 varieties were tested for resistance.[124] Only one was resistant, an Indian variety and known to science only since 1966.[124] This variety formed a hybrid with other varieties and is now widely grown.[124]
  • Coffee rust attacked coffee plantations in Sri Lanka, Brazil and Central America in 1970. A resistant variety was found in Ethiopia.[125] The diseases are themselves a form of biodiversity.

Monoculture was a contributing factor to several agricultural disasters, including the European wine industry collapse in the late 19th century and the US southern corn leaf blight epidemic of 1970.[126]

Although about 80 percent of humans' food supply comes from just 20 kinds of plants,[127] humans use at least 40,000 species.[128] Many people depend on these species for food, shelter and clothing. Earth's surviving biodiversity provides resources for increasing the range of food and other products suitable for human use, although the present extinction rate shrinks that potential.[103]

Human health

The diverse forest canopy on Barro Colorado Island, Panama, yielded this display of different fruit

Biodiversity's relevance to human health is becoming an international political issue, as scientific evidence builds on the global health implications of biodiversity loss.[129][130][131] This issue is closely linked with the issue of climate change,[132] as many of the anticipated health risks of climate change are associated with changes in biodiversity (e.g. changes in populations and distribution of disease vectors, scarcity of fresh water, impacts on agricultural biodiversity and food resources etc.). This is because the species most likely to disappear are those that buffer against infectious disease transmission, while surviving species tend to be the ones that increase disease transmission, such as that of West Nile Virus, Lyme disease and Hantavirus, according to a study done co-authored by Felicia Keesing, an ecologist at Bard College and Drew Harvell, associate director for Environment of the Atkinson Center for a Sustainable Future (ACSF) at Cornell University.[133]

The growing demand and lack of drinkable water on the planet presents an additional challenge to the future of human health. Partly, the problem lies in the success of water suppliers to increase supplies and failure of groups promoting the preservation of water resources.[134] While the distribution of clean water increases, in some parts of the world it remains unequal. According to the World Health Organisation (2018), only 71% of the global population used a safely managed drinking-water service.[135]

Some of the health issues influenced by biodiversity include dietary health and nutrition security, infectious disease, medical science and medicinal resources, social and psychological health.[136] Biodiversity is also known to have an important role in reducing disaster risk and in post-disaster relief and recovery efforts.[137][138]

According to the United Nations Environment Programme a pathogen, like a virus, have more chances to meet resistance in a diverse population. Therefore, in a population genetically similar it expands more easily. For example, the Coronavirus pandemic had less chances to occur in a world with higher biodiversity.[139]

Biodiversity provides critical support for drug discovery and the availability of medicinal resources.[140][141] A significant proportion of drugs are derived, directly or indirectly, from biological sources: at least 50% of the pharmaceutical compounds on the US market are derived from plants, animals and microorganisms, while about 80% of the world population depends on medicines from nature (used in either modern or traditional medical practice) for primary healthcare.[130] Only a tiny fraction of wild species has been investigated for medical potential. Biodiversity has been critical to advances throughout the field of bionics. Evidence from market analysis and biodiversity science indicates that the decline in output from the pharmaceutical sector since the mid-1980s can be attributed to a move away from natural product exploration ("bioprospecting") in favour of genomics and synthetic chemistry, indeed claims about the value of undiscovered pharmaceuticals may not provide enough incentive for companies in free markets to search for them because of the high cost of development;[142] meanwhile, natural products have a long history of supporting significant economic and health innovation.[143][144] Marine ecosystems are particularly important,[145] although inappropriate bioprospecting can increase biodiversity loss, as well as violating the laws of the communities and states from which the resources are taken.[146][147][148]

Business and industry

Agriculture production, pictured is a tractor and a chaser bin

Many industrial materials derive directly from biological sources. These include building materials, fibers, dyes, rubber, and oil. Biodiversity is also important to the security of resources such as water, timber, paper, fiber, and food.[149][150][151] As a result, biodiversity loss is a significant risk factor in business development and a threat to long-term economic sustainability.[152][153]

Leisure, cultural and aesthetic value

Biodiversity enriches leisure activities such as hiking, birdwatching or natural history study. Biodiversity inspires musicians, painters, sculptors, writers and other artists. Many cultures view themselves as an integral part of the natural world which requires them to respect other living organisms.

Popular activities such as gardening, fishkeeping and specimen collecting strongly depend on biodiversity. The number of species involved in such pursuits is in the tens of thousands, though the majority do not enter commerce.

The relationships between the original natural areas of these often exotic animals and plants and commercial collectors, suppliers, breeders, propagators and those who promote their understanding and enjoyment are complex and poorly understood. The general public responds well to exposure to rare and unusual organisms, reflecting their inherent value.

Philosophically it could be argued that biodiversity has intrinsic aesthetic and spiritual value to mankind in and of itself. This idea can be used as a counterweight to the notion that tropical forests and other ecological realms are only worthy of conservation because of the services they provide.[154]

Ecological services

Eagle Creek, Oregon hiking

Biodiversity supports many ecosystem services:

"There is now unequivocal evidence that biodiversity loss reduces the efficiency by which ecological communities capture biologically essential resources, produce biomass, decompose and recycle biologically essential nutrients... There is mounting evidence that biodiversity increases the stability of ecosystem functions through time... Diverse communities are more productive because they contain key species that have a large influence on productivity and differences in functional traits among organisms increase total resource capture... The impacts of diversity loss on ecological processes might be sufficiently large to rival the impacts of many other global drivers of environmental change... Maintaining multiple ecosystem processes at multiple places and times requires higher levels of biodiversity than does a single process at a single place and time."[104]

It plays a part in regulating the chemistry of our atmosphere and water supply. Biodiversity is directly involved in water purification, recycling nutrients and providing fertile soils. Experiments with controlled environments have shown that humans cannot easily build ecosystems to support human needs;[155] for example insect pollination cannot be mimicked, though there have been attempts to create artificial pollinators using unmanned aerial vehicles.[156] The economic activity of pollination alone represented between $2.1–14.6 billion in 2003.[157]

Biodiversity Ecosystem services articles: 58