英语听力:2013-03-22 恐龙之战之极限生存 Extreme Survivors—2(在线收听) |
I think it’s a very beautiful idea that you have this little egg that’s surprisingly small and out of it comes a baby sauroposeidon that’s about the size of a rabbit and in two or three decades, it’s gonna be a 50-ton adult. But why does this huge animal have such small eggs?
Sauroposeidon eggs like all eggs are honeycombed, with tiny pores to let oxygen in and carbon dioxide out. Bigger eggs need more air holes, but if they get too big, the shell collapses. That’s why even today no bird lays a larger egg larger than an ostrich which weighs just over a kilogram.
Each female lays about 500 eggs a season. The moment an egg hatches marks the beginning of a race for survival, a race that virtually all of them will lose.
Being a hatchling, you don’t have horns, you don’t have plates, you don’t have any kind of armor on your body. Practically, anything could gobble it up.
Thousands of defenseless hatchlings are left loose into a world of fierce predators. It’s a brutal way to raise a family.
Sauropods are just trying to flood the environment with babies, just in the hopes that a few survive.
In the cretaceous period, plant eaters face vicious killers. And none has a worse reputation than Tyrannosaurus Rex, possibly the largest land predator that has ever lived.
T-Rex is sort of the quintessential monster.
A dinosaur with an attitude.
A tyrannosaur as Rex can grow to 5.5 meters tall and 12 meters long with jaws designed to tear meat to shreds. |
原文地址:http://www.tingroom.com/lesson/yytltsfx/2013/245975.html |