英语听力：恐龙之战之极限生存—12

Like sea turtles who from the moment they hatch they are on their own. For predators, hatching time is a veritable feast. Even so, the strategy works. Carnivores gulp down virtually every hatchling, but a few do make it, not even the most voracious feeders can kill them all.

Sauropods were in a predator-rich environment, so I’m sure that many, many Sauropods nests were found and destroyed by predators before the babies could even hatch.

Sauroposeidon’s size is its main defense. When it reaches an adult weight of 50 tons, nothing can touch it. But maintaining this massive girth means filling up almost constantly. An adult will eat almost anything that grows. They consume as much as 330, 000 calories, almost a ton of greenery every day. To find that much food, herds roam great distances. Even if they had the brain capacity to care for their young, there just isn’t enough vegetation to let them stay by the nest.

How much of your resources do you put into reproduction, to producing the next generation? And it’s always a trade-off. If you put in a lot of parental care, then you don’t have the resources to make lots and lots of babies. Or you can go the other way, make tons and tons of babies, but you won’t have the resources left to take very good care of them.

Taking care of offspring requires not only brain power but also well-developed senses. Sauroposeidon has neither. Its eyes are separated, located on each side of its head, so it has no ability to judge depth. Its small brain has only rudimentary centers of sight and smell.