Paleocene dinosaur survivors

Dear All, It has finally been published. Will this new evidence convince the skeptics? We shall see.

Even if the extinction event was 99.999 percent total, that would mean that there STILL would have been survivors. Not sure that I understand how those survivors might have been in an area so 'relatively' close to the suspected impact point and survived, but, if this is what the rocks say, its what the rocks say!

Could have been as simple as a rookery protected by local mountains from the blast wave and/or tsunamis and cold enough to preserve but not hatch the eggs, etc, etc, etc. Lots of alternative explainations for the survival of 'the few', but. . . . didnt hang on for all that long.

If there was one species Id have bet on surviving it might have been one of the hadrosaurs based on the apparently huge numbers that were present and the fact that any survivors would need to eat just about any kind of plant life that survived. (and a hadrosaur's grinders could make pulp out of the hardiest shrubs.) as well as any tender shoots poking up through the deritus.

Regards

Snippage here.

Dr. Keith Rigby at Notre Dame proposed years ago that the small dino bones he had unearthed in unquestioned Paleocene strata in Montana were unreworked skeletal elements from dinosaur survivors of the K/T event. Of course, dino detectives such as Dr. Horner and others simply shrugged off the fragmentary Paleocene dinosaur remains and said, in effect, 'get back to me when you find a complete skeleton. Otherwise, it's all reworked crap, all sound and fury, signifying nothing, as it were.'

But, even in the face of several fossil skeletal elements (such as the cited Hadrosaur in New Mexico) one must be ultracareful about the veracity of such extravagant claims. Several years ago, for example, some researchers were convinced that plesiosaur remains unearthed from supposedly proved Paleocene-age rocks near Los Angeles (in the Cajon Pass region, that wonderful transition region in the San Bernardino Mountains between The LA Basin and the Mojave Desert) were not reworked, that they were in-situ proof that plesiosaurs, at least locally, had survived into the Tertiary. The case for a Paleocene age rested on some microscopic single celled animals present in the same rocks that held the plesiosaur remains

Bob, New Mexico is close enough to the Yucatan that *ALL* life on the surface would have perished (except possibly for a few bacteria, I suppose). Underground would have been a different matter. But as I have explained before, the most important key for end-Cretaceous survival (especially for birds and dinosaurs) may have been burial in alkaline soils, which would have helped to neutralize the acid rain which followed. The same goes for frogs. Those lucky enough to be buried in alkaline soils would have a definite advantage over those in neutral or acidic soils. If the crash site had been less acidic, the outcome would have been somewhat different, as the acid rains would have been less strong. A 99% percent extinction might have only been a 95% extinction, and maybe ammonites or enantiornithine birds would have made it through. Who knows?

Actually, the 'microscopic single-celled animals' were dinoflagellates.

(SNIP)

I'm sorry, did they just suggest the eggs had a one to two year gestation period?

I would change 'would' to 'could' perhaps.

Well, I know that there are examples of some frogs that bury themselves in bottom mud and go 'dormant' over very long periods of arid conditions, years or more, as do some lung fish (IIRC), but I know of no higher animals that pull off that trick. That was why I was muddling over the idea of preserving eggs in cold and thereby extending the 'hatch date'.

The other possibility might be that the cataclysmic events following the impact MIGHT not have lasted any longer than the normal gestation period fro hadrosaur eggs. In other words, the nests laid down 'the day before' may have simply kept the fetal hadrosaurs all wrapped up in egg shell 'environmental suits', burried underground for the duration of the really ugly after-effects!

Now lets get wierd for a moment! Could the absence of the large predators possibly indicate that they were vivaporous, as based on the fossil recored were the icthyosaurs? The idea being that vivaporous obviously would not have that pseudo-dormant 'protected' egg stage.

My pet challenge is for someone to offer up an airbreating species weighing more than 10kg that survived KT unchanged. Perhaps this is still the one to match that challenge, by whatever means of survival it was afforded. I think that I still want some more info though before I pay off the bet! )

Regards

A reasonable assumption, but by no means proven. New Mexico is more than 1000km from Yucatan. That's beyond line of site even from the top of the atmosphere, so radiation and radiation and radiation triggered fires are probably not an issue. AFAIK, there is no evidence of massive bombardment by fragments, no layer of choking dust, and no evidence of inundation by salt water at the KT boundary there. The continent cleansing tidal waves of the tabloids probably didn't happen. Even assuming there was enough water available to create a kilometer high tsunami, if it acted like a normal wave it probably wouldn't run out more than 25-50 km beyond the beach. ISTR that the tsunami height at the Brazos River KT sites somewhat closer to the impact is estimated around 100m.

Without knowing exactly how the asteroid caused the extinction

How about Champsosaurus Natator? Estuarine, but definitely airbreathing, with large specimens prob exceeding 10kg by a significant margin.

Found plenty of citations for U. Cretaceous, but for after the KT event?

Defintely meets my size criteria, but cant find reliable citations for post-KT deposits.

If you have some. . . . . . 8-)

Regards