To prevent the well known and well documented problems of genetic defects caused by in-breeding, species need a variety of genes to ensure successful survival. Without this, the chances of extinction increases. And as we start destroying, reducing and isolating habitats, the chances for interaction from species with a large gene pool decreases. Side Note Unfortunately the original link to the Nature.
However, for similar information, you could look at Consequences of changing biodiversity , Nature , - , 11 May and Causes, consequences and ethics of biodiversity , Nature , —, 11 May While there might be survival of the fittest within a given species, each species depends on the services provided by other species to ensure survival.
It is a type of cooperation based on mutual survival and is often what a balanced ecosystem refers to. The relationship between soil, plants, bacteria and other life is also referred to as the nitrogen cycle:. As an example, consider all the species of animals and organisms involved in a simple field used in agriculture. Shiva, a prominent Indian scientist and activist goes on to detail the costs associated with destroying this natural diversity and traditional farming techniques which recognize this, and replacing this with industrial processes which go against the nature of diversity sustainability.
Bees provide enormous benefits for humankind as another example. As reported by CNN May 5, , One third of all our food—fruits and vegetables—would not exist without pollinators visiting flowers. But honeybees, the primary species that fertilizes food-producing plants, have suffered dramatic declines in recent years, mostly from afflictions introduced by humans.
Bees are vital to bio diversity. There are , plants for example for which bees are essential to pollination, from melons to pumpkins, raspberries and all kind of fruit trees — as well as animal fodder — like clover. Researchers are finding reasons for the massive decline hard to pinpoint, but suspect a combination of various diseases, environmental pollution, environmental degradation leading to less diversity for bees to feed from, for example and farming practices such as pesticides, large monoculture cropping, etc.
The link and dependency between plants, bees, and human agriculture is so crucial, the two scientists writing up years of research into the problem summarized with this warning:. Humankind needs to act quickly to ensure that the ancient pact between flowers and pollinators stays intact, to safeguard our food supply and to protect our environment for generations to come.
These efforts will ensure that bees continue to provide pollination and that our diets remain rich in the fruits and vegetables we now take for granted. An example from the seas originally mentioned here years ago but removed because the link to the story no longer worked , was described by National Geographic Wild in a program called, A Life Among Whales broadcast June 14, It noted how a few decades ago, some fishermen campaigned for killing whales because they were threatening the fish supply and thus jobs.
A study in the journal Science , notes that these large animals — such as lions, leopards, wolves and bears — are in decline, due to declining habitats and persecution by humans.. This also has a negative impact on the environment, perhaps partly formed by outdated-views that predators are harmful for other wildlife.
As a simple example, the loss of a large carnivore may mean in the short term the herbivores they prey on may increase in numbers but this can also result in a deterioration of the environment as the herbivores can graze more, largely unchecked. Human intervention to perform the same services would be more costly. Nature can often be surprisingly resilient, often without the need for human interventions.
For example, a documentary aired on the BBC I unfortunately forget the name and date, but in the s described two national parks in Africa where elephant populations had grown quite large within those artificial boundaries. The usual way to deal with this was to cull the population to try and keep the ecosystem in balance.
Without this, elephants were stripping vegetation bare, affecting other animals, too. A scientist pleaded with park management not to cull and let nature take its course. Being against prevailing thought, they would not agree. In the end they agreed to let one park have its elephants culled, while the other would be left alone. In other words, Mayr was using the idea of reproductive separation of species to answer both the "what" and the "how" questions about identifying species Mayr To Mayr, the key to identifying species is determining whether there is shared reproduction within a population of organisms and whether there are barriers to reproduction with other organism.
Beldade, P. The genetics and evo-devo of butterfly wing patterns. Nature Reviews Genetics 3, Cracraft, J. Species concepts and speciation analysis.
Current Ornithology 1 , Ernst Mayr and the modern concept of species. PNAS Suppl 1 , Donoghue, M. A critique of the biological species concept and recommendations for a phylogenetic alternative.
The Bryologist 88 , Federal Register. Hey, J. The mind of the species problem. Trends in Ecology and Evolution 16 , Mayr, E. Species concepts and definitions. The Species Prblem. AAAS, Washington, Rosen, D. Fishes from the uplands and intermontane basins of Guatemala: revisionary studies and comparative biogeography.
Bulletin of the American Museum of Natural History , Rosenbaum, H. World-wide genetic differentiation of Eubalaena : questioning the number of right whale species. Molecular Ecology 9 , Templeton, A. The meaning of species and speciation: a genetic perspective.
Speciation and its consequences. Sinauer Associates, Sunderland, MA Origins of New Genes and Pseudogenes. Evolutionary Adaptation in the Human Lineage. Genetic Mutation. Negative Selection. Sexual Reproduction and the Evolution of Sex.
Haldane's Rule: the Heterogametic Sex. Hybrid Incompatibility and Speciation. Hybridization and Gene Flow. Why Should We Care about Species? By: Jody Hey, Ph. Citation: Hey, J. Nature Education 2 5 The questions "What are species? See how consensus on answers to these questions can steer global, political, and financial pressures that affect conservation efforts. Aa Aa Aa. Why Are Species So Confusing? The central difficulty when studying species is that, even though all species are kinds of organisms, all kinds of organisms are not species.
For example, birds are a kind of organism, but birds are not a species --there are many thousands of species of birds.
For scientific purposes, it is not enough to identify a kind of organism. As a biologist you must also determine what level or rank of kind to assign to an organism. If you discover a new kind of organism then you must decide if it should be called a new species, or if it falls within an already described species. For example, the common chimpanzee species, Pan troglodytes , appears to include several slightly different kinds of chimpanzees.
Each of these have been given the rank of sub-species. Alternatively, a newly discovered kind of organism might be so different from other known species that it receives not only a designation as a new species but also a ranking as a new genus. To help understand the confusion and uncertainty over species, let's look at the most basic idea of Darwin's theory of evolution by natural selection. Darwin figured out a process by which species could change over time, and he believed that evolution was a slow and gradual process that played out over eons of time.
So if species are changing slowly, and if new species are formed at the slow pace of evolution, then we absolutely expect there to be cases where we struggle to decide whether two kinds of organisms should be grouped as separate species or as a single species.
In his book, On the Origin of Species , Darwin famously wrote, "I was much struck how entirely vague and arbitrary is the distinction between species and varieties.
In other words, Darwin did not believe that there was a definite point at which a species came into existence.
Finally, because the large majority of species come into existence gradually, it is not surprising that we have difficulty deciding when to identify new species or what the best way to do so should be. What Is a Species? Figure 1: Variation within species. Within the same species, individual organisms can look very different. For all three species of butterflies , wing color and pattern varies depending on the season during which they were born.
The butterflies at the top were born under different temperature and light conditions than the ones at the bottom. Paul Brakefield. All rights reserved. If undamaged, this produces a finely balanced, healthy system which contributes to a healthy sustainable planet. The sheer richness of biodiversity also has human benefits. Many new medicines are harvested from nature, such as a fungi that grows on the fur of sloths and can fight cancer.
Wild varieties of domesticated animals and crops are also crucial as some will have already solved the challenge of, for example, coping with drought or salty soils. From an aesthetic point of view, every one of the millions of species is unique, a natural work of art that cannot be recreated once lost.
Mind-bogglingly diverse. The simplest aspect to consider is species. About 1. The heartland of biodiversity is the tropics, which teems with species. In 15 hectares 37 acres of Borneo forest, for example, there are species of tree — the same number as the whole of North America.
Recent work considering diversity at a genetic level has suggested that creatures thought to be a single species could in some cases actually be dozens. Then add in bacteria and viruses, and the number of distinct organisms may well be in the billions.
The concern is that many species are being lost before we are even aware of them, or the role they play in the circle of life. The best studied creatures are the ones like us — large mammals.
In many places, bigger animals have already been wiped out by humans — think dodos or woolly mammoths. The extinction rate of species is now thought to be about 1, times higher than before humans dominated the planet, which may be even faster than the losses after a giant meteorite wiped out the dinosaurs 65m years ago. The sixth mass extinction in geological history has already begun , according to some scientists.
Species extinction provides a clear but narrow window on the destruction of biodiversity — it is the disappearance of the last member of a group that is by definition rare. The results are scary. Billions of individual populations have been lost all over the planet, with the number of animals living on Earth having plunged by half since Humans may lack gills but that has not protected marine life.
The situation is no better — and perhaps even less understood — in the two-thirds of the planet covered by oceans.
Seafood is the critical source of protein for more than 2. Altogether, there are at least a million species of insect and another , spiders, molluscs and crustaceans. And insects really matter, not just as pollinators but as predators of pests, decomposers of waste and, crucially, as the base of the many wild food chains that support ecosystems.
Even much-loathed parasites are important. One- third could be wiped out by climate change , making them among the most threatened groups on Earth.
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