Quoting nielsen <[log in to unmask]>:

>  in practice I think it is still useful.
> Otherwise, how do you differentiate if a type species is a living or a
> fossil one? If the type species is, say, Miocene or what? Holocene? It
> wouldn't do it justice, I think.

* remember that the "-cene" in the names of the epochs refers to the
percentage of living Mollusc species in the fossil record "The Miocene
was named by Sir Charles Lyell... from the Greek words mei&#333;n
(“less”) and kainos (“new”) and means "less recent" because it has 18%
fewer modern sea invertebrates than the Pliocene." - wikipedia

fred.
===================================================

> Am 2014-01-06 18:25, schrieb Powell, Charles:
>> Sevn,
>>
>> I think your mixing up two different things. ? Extant and extinct
>> refer to if an animal or plant is still living today or not.
>> ? Holocene, Pleistocene, Pliocene, etc are ages, periods of time in
>> the past. ? Animals can be living today and range back in time to the
>> Pliocene or older (the are still extant), while a few known from the
>> Holocene, from within a few hundred years of present are still
>> extinct
>> because there are no representatives of the species still alive. ? One
>> set of terms is completely different from the other and they
>> describes
>> different things. ?
>>

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