/sci/ - Science & Math

>>16040889
>What the hell is a virus?
They seem to me to be similar to inert exossomes, or bits of genetic code that can bounce around outside of cells until they can become active within cells.
They are not alive since they cannot consume organic matter or radiation to grow or reproduce.
However, the system virus+host cell could be considered a sort of "unbounded" living thing, since it does consume energy (the host cell) which is used in producing more copies of the virus.

>>15914708
>Their bones were hollow, they had air sacs inside them to lighten them up and allow them to move about at the size they got.
Yes, but convergent evolution would have taken care of that by now.
>We don’t have massive continents with mostly the same biome everywhere
Pagea was huge, it had plenty of geographical variation, it reached from the arctic to the antarctic circles, it had much topographical variation, and just as much coastal diversity, and the Jurassic + Cretaceous ages lasted for 145M years. It's simply impossible for the climate to remajn stable over such a vast continent, and such long duration.
What I am reading, and it makes some sense is that grasses had not yet evolved in the Jurassic, and vegetation seems to have beem mostly trees and tree-like plants, and in lacking competition from grasses, tress might have had the opportunity grow truly large, providing a large supply of plant matter for gigaherbivores to evolve. Plus, size is defense, yet another evolutionary force vector.
But, again, too vast of a time period, too vast of a continent for such broad statements.
Something very, very strange indeed happened in the Jurassic for giant sauropoda to evolve, very unique conditions permitted such evolutionary excesses. The Cretaceous doesn't surprise me as much since once that megafauna had evolved, it could have diversified and adapted to many different other environments over the many tens of millions of years.
Pity, it'd be so awesome to see something like that walk around nowadays.
Picture unrelated.