4boards

https://www.nature.com/articles/srep18952
Researchers some years ago found in the Dakota Formation of Colorado (Cenomanian age, good for preserving trackways and some plants, less so skeletons) strange collections of footprints scraping the ground. The prints were identifiably those of a three-toed ~16 foot theropod and there were collections of adults/subadults of various sizes in the same place, preserved well. These scrapings are most similar to those formed by modern shorebirds in mating leks.

>The sharply-terminated scratch marks found in association with diagnostic theropod tracks represent active theropod scraping or scratching. The most complete theropod tracks include a large Irenesauripus-like27,28 left theropod track on the left side of the holotype scrape (Fig. 3a) and a smaller right theropod track associated with the right side of a shallow paratype scrape (Fig. 3c). The variable size and depth of the scrapes, indicate different levels of activity and persistence by different sized theropods, which based on footprint length had hip heights between ~1.0 and ~2.0m29 and full body lengths between ~2.5 and ~5.0m. This implies either two or more different species, or co-occurrence of conspecific adults and sub-adults of quite different sizes. Elapsed time between scraping episodes cannot be estimated accurately, but was likely short given the similar, good preservation of all scrapes.

If it is true that a 2.5-5m long obligate carnivores were lek mating in a specific spot and scraping to impress the ladies, and each area has up to 60 PRESERVED scrapes, how were so many large predators in the same place? You don't get a dozen polar bears all in the same place trying to get laid. What are all the dinos eating? modern apex predators have low population densities. Is the radius out from the site to get food practical for them all to eat? Is this a sign that large theropods had slower metabolisms than mammal predators? Do crocodilians lek at all?

NFT

#1526

Status

AVAILABLE

Random mint

$2.00 in SOL

Replies

1 / 1 images

[View Thread] [Mint Random]