Holocene extinction event

The Holocene extinction event is the name given to the widespread extinction of species occurring in the modern era, some defining the start of the era with the dying off of the species Homo neanderthalensis. The rate of extinction today appears to be similar to, or perhaps greater than, the rate during "classic" extinction events in the past, such as the one between the Devonian period and Carboniferous.

Large numbers of species have recently (in geologic terms) become extinct. Around 10,000 years before the present, thirty-nine mammalian genera disappeared, almost all of them large-bodied megafauna, including

• native American horses
• a few species of camels
• several types of large ground sloth[?]
• several antelope species
• "short-faced" bears (larger than the present grizzly), e.g. the Cave Bear
• sabertooth cats
• the American lion (larger than the current African lion)
• various species of mammoth
• the American Mastodon, Mammut americanum
• dire wolves
• diprotodons (giant relatives of the wombats)
• Zygomaturus trilobus (a large marsupial herbivore)
• Palorchestes azael (a marsupial "tapir")
• Macropus titan (a giant kangaroo)
• Procoptodon goliah (a hoof-toed giant short-faced kangaroo)
• Wonambi naracoortensis (a five-to-six-metre-long Australian constrictor snake)
• Thylacoleo carnifex (a leopard-sized marsupial lion)

Some prehistoric extinctions may be the sources of cryptozoological legends.

Such extinctions have continued to the present day. Within the last millennium, many other species have died off, such as

• the aurochs
• Thylacinus cynocephalus (the Thylacine or Tasmanian Tiger)
• many extinct birds, notably the Passenger Pigeon
• Steller's Sea Cow
• Dodo

Many claim that the current high extinction rate is mostly due to human activities. There still is debate as to the extent to which the disappearance of megafauna since the end of the last ice age can be attributed to human activites. While climate change is still cited as an important factor, such anthropogenic explanations are predominant.

Although there is a consensus among scientists that current extinction rates are above the average background levels, there is still much debate about the likely amount of human-caused extinction. Estimates range from mild to very severe.

In addition, all previous extinction events ran their course for several hundred thousand to several million years. Even those that were caused by sudden events, such as an asteroid impact, take a long time due to the complex ecological interactions that are upset by the event. So even if the current rate of extincition is higher than the rate during a great mass extinction event, if the current rate does not last more than a few thousand years, the overall effect will be small. There is still hope, argue some, that humanity can eventually slow the rate of extinction back to background levels through proper ecological management. Current socio-political trends, argue others, indicate that this idea is overly optimistic.