Earth may be up to 140,000 extinctions a year now

The Holocene extinction, sometimes called the Sixth Extinction, is a name proposed to describe the ongoing extinction event of species during the present Holocene epoch (since around 10,000 BCE) mainly due to human activity. The large number of extinctions span numerous families of plants and animals including mammals, birds, amphibians, reptiles and arthropods. Although 875 extinctions occurring between 1500 and 2009 have been documented by the International Union for Conservation of Nature and Natural Resources,^[1] the vast majority are undocumented. According to the species-area theory and based on upper-bound estimating, the present rate of extinction may be up to 140,000 species per year.^[2]

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Holocene extinction

 

The majority of different species on earth on both land and sea and fresh water no human likely has ever seen or registered. So, mankind has only registered with a name a fragment of species here on land and water. Using  species-area theory (use word button to learn more) the likely rate of extinctions now is 140,000 species a year which might compare to when all the large dinosaurs died when an asteroid hit earth within a few years. They either froze to death, or starved to death because a nuclear winter type of event occurred where the sun was blotted out for years where they lived. 

I was actually surprised that as many species died in the ocean as on land because I hadn't understood this before. However, I do know species like Whales, crocodiles, sharks, dolphins likely survived this time or were some type of aquatic life that evolved from there.

Also, many scientists think that Sea Elephants were once bears that adapted to water maybe during this time or later and sea lions might have been wolves who adapted to water over time etc.

My thought is that dolphins might have been related to humans and adapted to water because of their advanced intelligence. Pigs are extremely intelligent also and are similar to humans in many ways so they also might be related to humans way back.