It's a complex mix definitely.. On one hand, increasing population is pushing man to invade animal territory in search of land for competitive uses. On the other hand, man feed on some of these animal far more than their rate of reproduction, hence sustainability becomes an issue. And important, in the quest of man's survival and comfort, the environment is been affected in a way that is continuing shaping the planet ecosystem causing global warming. The change reaction affect the animals a large extent causing migration and possibly die off. Like I said earlier, it a complex mix. But one thing is more of a real culprit here, "Man, and his activities".

As per me its not only the climate change but many other factors which are pushing species towards extinction. I would answer in terms of Himalayan species. Surely climate change is one of the major reason including pollution other than this are growing human population causing many other side effects on the ecosystem such as deforestation and urbanization, habitat degradation/fragmentation. Reduction in agricultural practices and loss of traditional ecosystem management practices are also very important factors and above all poaching and hunting of endangered animals to fulfill human greed. Examples are many as Himalayan quail (Ophrysia superciliosa). Some more species like Himalayan Monal ( Lophophorus impejanus) and Alpine/Himalayan Musk deer (Moschus chrysogaster), Golden Mahseer (Tor putitora) etc. are next.

Sometimes it's naturally too as its the rule of nature that a species extincts and a new arises. For this the competition among species as well as the natural calamities push a species towards extinction.

Dear Ajit,

At present, the loss of biodiversity and related changes in the environment are faster than at any time in human history. Many animal and plant populations are declining, whether in terms of numbers, geographic extent, or both. The disappearance of species is part of the natural course of Earth's history. However, human activity has accelerated the natural rate of extinction. Recent studies estimate that the extinction rate of vertebrates today, even under stable conditions, is 100 times higher than their natural extinction rate (Ceballos et al., 2015). Unfortunately, the loss of biodiversity continues to accelerate, as shown by the successive reports of Living Planet WWF. The current extinction, caused by human activities, is comparable to a major biological crisis since by 2050, it is considered that 25 to 50% of the species will have disappeared, including in the oceans. Almost everywhere human societies have settled and flourished, large animals have been slaughtered, ecosystems sustainably polluted and the habitats of other species destroyed. However, several million years are needed to cover a biological diversity following a massive extinction.

Thus, the unsustainable activities of our societies have begun a mass extinction that should definitely seal the fate of humanity: we will be both the cause and the victims of this sixth mass extinction ...

With my best regards

Prof. Bachir ACHOUR

Yes climate change contributes a lot for species extinction. The Darwin theory works "The survival of the fittest". On the other hand unprecedented intervention of humans and animals contribute for extinction. Agricultural modernization and utilization of rich biodiversity areas for agricultural activities also contributes a lot. The other factor may be deforestation (fire, land clearing, etc). In general climate change and human intervention are the significant contributors for species extinction.

No doubt climate change is one of the reason but besides climate change, destruction of habitat, habitat fragmentation, environmental pollination, introduction and invasion of exotic species, introduction of competing or predatory species, over-exploitation, hunting, deforestation, over-grazing, disease, collection for zoo and research and control of pest and predators are the other reasons which are pushing species towards extinction.

thanks drs. Naveen, Bachir,Beemnet,Kenneth and Arvind for adding valuable answers.

Yes climatic changes do count for this

Biodiversity changes follow a complex pattern of eco-system related changes in time. Locally this will be foremost the availability of water, food, habitats, shelter and breeding places, pressure of other species, a least number of population of the concerned species for replication (genetic pool) etc. On a higher dimension factors such as overall landuse change, pressure of anthopogenic developments (e.g. highways, traffic, barriers such as roads, fences etc) disrupt the ecology system whereas closennes to human settlements means increasing pollution. Climate related changes add surely, especially changes in water cycle, increasing temperatures, seasonal changes, impacts of increasing weather hazards such as drougths, storms, typhoons etc. This list of potential parameters is far from complete. However, the various levels of potential impacts from i) local, ii) regional and iii) global (e.g. climate change; changes in marine currents and temperatures such as El Nino / El Nina) need to be sorted out and their interdependence analyzed / understood. This speaks for "big data gathering and anaylsis" from my perspective.

Thank u Dr Paul for valuable answer.

interaction is indeed useful Dr Kenneth

Dr. Kenneth I would like to add that as human population is increasing more space is needed for shelter, agriculture and industries where is the land coming from and whose habitat is it ours or animals? Is it not anthropogenic? Habitat loss and fragmentation as well as deforestation think about carbon stock?

It's a complex mix definitely.. On one hand, increasing population is pushing man to invade animal territory in search of land for competitive uses. On the other hand, man feed on some of these animal far more than their rate of reproduction, hence sustainability becomes an issue. And important, in the quest of man's survival and comfort, the environment is been affected in a way that is continuing shaping the planet ecosystem causing global warming. The change reaction affect the animals a large extent causing migration and possibly die off. Like I said earlier, it a complex mix. But one thing is more of a real culprit here, "Man, and his activities".

thanks dr Victor and dr Naveen for answers

thank u dr Kenneth for nice input

Kenneth gave as examples of extinct species the Dodo (last cited 1662) and the Passenger Pigeon (circa 1914). The IUCN (International Union for the Conservation of Natural and Natural Resources) performs global assessments of species status every 5 years (or 10 for some species). If you go to this page (http://www.iucnredlist.org/about/summary-statistics) and go to the bottom of the page, you will see a heading “Possibly Extinct Species”. Under that heading, there is a link to IUCN Table 9, Possibly Extinct and Possibly Extinct in the Wild Species. On that list, you will find 43 species listed as possibly extinct or extinct in the wild AFTER 1916.

In addition to my first comment were I summarized in more general the multi-lateral conditions/reasons that may push species towards extinction I would like to add: Related to the increasing pressure from anthropogenic interventions it is foremost pollution and ongoing development of synthetic (un-natural) materials and products! Climate change is a consequence of anthropogenic pollution due to uncontrolled emission of climate relevant gases/particles. Marine pollution (plastic emissions, overloads of nutritients and persistant pollutants) may drastically add and push marine species towards their ecological limits even before climate change effects trigger negeative effects for their eco-system.   

I fully agree with your viewpoints Dr Kenneth

thank u dr Michael and Dr Paul for nice input

Kenneth uses the example of invasive species effect on species loss. Invasive species is an example of human effects on ecosystems since humans introduce the invasive species, and thus this example is not a counter-example.

There is a significant literature on extinction rates comparing anthropocene extinct rates with extinction rates discoverable from fossil records. Some of that literature is written by eminent scientists such as Will Steffen, Paul J. Crutzen, etc.,. I am not going to review this literature and the various arguments, but I suggest that an in depth reading of that material is important to this question since it discusses the specific nature of this question.

The fact that new species are discovered has little to do with the rate at which known species become extinct. It is, for example, likely that there may be many undiscovered extinct species that were never found. The unknown cannot be estimated.

The term “possibly” is, of course, a scientific qualification, as scientists do not often speak in absolute, unqualified, terms.

It doesn't matter that the discovery of new species exceeds the rate of extinction. These are independent measures. There are undiscovered species that have become extinct, and if they are not preserved in, for example, some kind of fossil or other record, we don't know about the extinction rate of undiscovered species. It is entirely possible, foe instance, that small previously unobserved species have become extinct, so we don't know about the rate of extinction among unobserved species.

As for factors affecting species extinction, there are many correlates that are driven by humans: habitat loss (e.g., from urban expansion; draining wetlands; deforestation) habitat fragmentation (which is related to, but not the same as habitat loss); expansion of agriculture; pollution (e.g., acid rain; chemical/waste spills); poaching/hunting; changes in water quality (e.g., salinity; pH; other aspects of chemical composition); introduction of invasive species, diseases, parasites, fungus, by humans;

thanks dr Kenneth and Dr Michel for useful interactions.

I agree with the earlier submissions. I believe extinction of species is based on urbanization and evolution. As the world urbanize some species just fail to evolved and they extinct. Dinosaurs lived millions of years ago but where are they; they just could evolve along.

Indiscriminate killing/poaching.

Habitat modification and destruction via constructional projects

Unrestrained harvesting and failure of conservation agencies in regulating the onset/ duration of harvest of biodiversity species

Failure of ensuring patch-switching by authorities in maximizing overall returns

Weak legislation and enforcement of laws regarding the sustainable use of biodiversity species by implementation agencies.

Thanks Dr. Kenneth for the knowledge.

Everyone has made one valid point or the other, and the fact remains that it is a "complex mix". We can only suggest as many reasons as possible, however we can't categorically say the extent of impact of each and every individual factor. Why we know that some factors are more detrimental than others, we should focus on those we have direct influence on. Which is basically reducing our carbon imprint. Every other reason may just end as an academic exercise with no real time solution. Even global warming would take a lot of commitment to see meaningful control.

And to answer Dr. Kenneth's question.

Yes, many species have possibly gone extinct even before they are discovered. However, while we intensify efforts to name new species, we must continue to put up measures that protect the already known once.

right dr Victor

I agree with you Dr Dickson Adom.

Regards!

Correct.

thanks dr Kenneth