What would you thinking about if we create a new subcategory for species where it is difficult to classify them either in the Pleistocene or in Holocene period. Adzebill has posted some examples in the Extinct birds category today. Or we put all Pleistocene or unkown Pleistocene / Holocene border extinctions in that category which we can name Quarternary extinctions or similar.
P.S. I deleted the posts about Aquila nipaloides and Tuto mourerchauvieae that I wrongly opened in the recent extinctions and re-writed then in prehistoric extinctions, as these species seen to be Pleistocene extinctions.
Well my idea was to put Pleistocene extinctions which were 100.000 years ago (e.g. species which became extinct by humans and the climatic changes in Australia) and species which have been found in deposits in South America, Central America or the Caribbean in that division. Expecially at the latter it is difficult to say whether they became extinct in Pleistocene or in Holocene because cave deposits of different periods were often merged in a way that you cannot determine an exact extinction period.
My suggestion for the structure would be:
Prehistoric Extinctions Quarternary Extinctions (100.000 to 10.000 years ago) Recent Extinctions
I'm not making a Quarternary Extinctions board, because that period stretches from the end of the Pliocene Epoch roughly 1.8-1.6 million years ago to the present. The Quaternary includes 2 geologic subdivisions: the Pleistocene and the Holocene Epochs.
It would be confusing for users when in the Quaternary extinction only extinctions are found that are between about 100.000-10.000.
When creating a Pleistocene category, we would have the same problem with uncertain extinction dates as between the Pleistocene-Holocene border.
Therefor I've created a Pleistocene-Holocene Border Extinctions category. Here the animals (and possible plants) can be placed that have an uncertain extinction date.
because than you keep the same problem, with having species that became extinct on the border of two periods. Than again it can be unclear in which period it became extinct. Besides that, would that not be too many boards?
Well as you all can see, I created a Category and board for the unclear Pleistocene-Holocene extinctions on your request. If you have a species for which it is unclear whether it became extinct in the Pleistocene ("prehistoric") or survived into the Holocene ("recent") period until it became extinct, you can move or post that in this new board.
Using a lot of boards for all the different periods or using different dates/periods in a certain period will be very unclear for visitors that are not familiar with these events/dates. I know for some the distinction between the Holocene ("recent") and "prehistoric" categories is already difficult. This forum must be open and accessible for all users!
Holocene category: all species that became extinct in the Holocene (starting about 12.000 years ago). Pleistocene-Holocene Border Extinctions category: all species for which it is unclear whether it became extinct in the Pleistocene ("prehistoric") or survived into the Holocene ("recent") period until it became extinct Prehistoric category: all species that became certain extinct before the Holocene ("recent") period.
I there is not need for such a board which I created, that I will delete it again.
Melanie suggested a different period for species that becam extinct between about 100.000 - 10.000 years ago (roughly Late Pleistocene).
Another option would be to rename the Holocene board into the Fifth extinction.
Fifth extinction: We can divide the Sixth Extinction into two discrete phases: * Phase One began when the first modern humans began to disperse to different parts of the world about 100,000 years ago. * Phase Two began about 10,000 years ago when humans turned to agriculture. Source: www.actionbioscience.org/newfrontiers/eldredge2.html
What are your thoughts on the Pleistocene-Holocene Border Extinctions board and what I just wrote this? As always I would appreciate all comments and opinions.