[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: [dinosaur] How many end-Cretaceous dinosaur genera were there

Using Walker's Mammals of the World I have done a rough count of mammals in the dinosize range of a quarter kilogram on up and got around 1000 species, excluding those from tundra polar habitats that were not around back then. On the other hand the megafauna killed off by humans in the last 50K years were not included. And maybe those mammals under a kg should be dropped because the non avian dinosaurs under that level were preavian theropods. And today the range of habitats is greater than back then, more mountain highlands, grasslands, etc. So it is probable that at a given time the non avian dinosaur species numbered in the mid or high hundreds, and the 600-1000 estimate is plausible, but maybe a little high. It is very unlikely that bird diversity was anywhere close to modern levels in those primitive times, probably in the hundreds or low thousands. 

It's the Starrfelt & Liow estimate (Philos Transactions 2016) that just 2000! non avian dinosaur SPECIES that were extant in the ENTIRE Mesozoic that is bogus. How did that get past review? Was more like tens of thousands of species. Might do a short paper on that. 


-----Original Message-----
From: Ruben Safir <ruben@mrbrklyn.com>
To: dinosaur-l <dinosaur-l@mymaillists.usc.edu>
Sent: Sun, Dec 4, 2016 12:40 am
Subject: Re: [dinosaur] How many end-Cretaceous dinosaur genera were there

On 12/04/2016 12:14 AM, Ruben Safir wrote:
> On 12/03/2016 10:53 PM, Mike Habib wrote:
>> There are about 11,000 species of named living bird species, but I wouldn't use that as a gauge for the likely number of non-avian dinosaurs at any time interval. Species density within clades is always highly uneven.
> Mike, think about it. The earth was richer then. How many mammals are
> there now?
According to Mammal Species of the World, 5,416 species were known in
2006. These were grouped in 1,229 genera, 153 families and 29 orders

from wikipedia...

and I bet that is a severe underestimate of the number of mammal species
alive today.

I have no idea how they get 628 to 1076 but if it is based on the
thought that we have anything near a complete image of the fauna from 70
million years ago (after a comet smashed a huge hole into the earths
crust the size of the midwest), then I think you need to reconsider.

and who said birds weren't to count as dinosaurs. think about how many
species were discovered just since you have entered the field. And you
have lost whole continents.

>> --Mike
>> Sent from my Cybernetic Symbiote
>>> On Dec 3, 2016, at 7:18 PM, Ruben Safir <ruben@mrbrklyn.com> wrote:
>>>> On 12/03/2016 10:12 PM, john-schneiderman@cox.net wrote:
>>>> I am not aware of any current world-wide census of terminal late Cretaceous Dinosaur genus/species. But there is an estimate of between 628 and 1076 dinosaur species existed prior to the K-Pg event. I'm referencing the study by Jean Le Loeuff
>>> Does that make sense? How many bird species are there today?

So many immigrant groups have swept through our town
that Brooklyn, like Atlantis, reaches mythological
proportions in the mind of the world - RI Safir 1998

DRM is THEFT - We are the STAKEHOLDERS - RI Safir 2002
https://urldefense.proofpoint.com/v2/url?u=http-3A__www.nylxs.com&d=DgIC-g&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=JMxjjbIZXCWilersPs1bzRx-3mUwTiQUzlyzWk7v7k4&m=7ohZfSSl11tsX_CUI1LyhtYQnTev3k86CLV5p2R2e6s&s=_9j9X6JYpBA4iVZmR8XT69w8vXSUA5ps4ptU6UEqooQ&e= - Leadership Development in Free Software
https://urldefense.proofpoint.com/v2/url?u=http-3A__www2.mrbrklyn.com_resources&d=DgIC-g&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=JMxjjbIZXCWilersPs1bzRx-3mUwTiQUzlyzWk7v7k4&m=7ohZfSSl11tsX_CUI1LyhtYQnTev3k86CLV5p2R2e6s&s=5fxbm-g7vGSvItbP-jL7TRKBU9BVMcXjO54m6xUHLIw&e= - Unpublished Archive
https://urldefense.proofpoint.com/v2/url?u=http-3A__www.coinhangout.com&d=DgIC-g&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=JMxjjbIZXCWilersPs1bzRx-3mUwTiQUzlyzWk7v7k4&m=7ohZfSSl11tsX_CUI1LyhtYQnTev3k86CLV5p2R2e6s&s=NaTZRIOaO7wMKbd0BeTXV7SOnWhrNNTYArT2XGf1OSc&e= - coins!

Being so tracked is for FARM ANIMALS and and extermination camps,
but incompatible with living as a free human being. -RI Safir 2013