When an animal leaves more offspring, its genes will spread.

当动物殖后时， 就意味着它们的基因得到传播。

For years, palaeontologists have wondered if the same was true of plesiosaurs.

数年来，古生物学家一直想知道蛇颈龙是否也通过怀胎方式殖后。

At that age, they reach sexual maturity, meaning the fish were able to produce young.

它们在这个年龄达到性成熟，这意味着它可以殖后。

The hope is that the oysters will help clean the water and also have babies.

人们希望这些牡蛎能够帮助清洁海水并殖后。

Question 2. To mate and then produce young animals.

交配，然后殖后。

And she added that it also allows them to reproduce more throughout their life.

“这也让它们在一生可以中殖的后。”

First, some organisms reproduce asexually, so they don't need other organisms to produce offspring.

首先，有些生物是无性殖的，所以它们不需要其他生物来殖后。

Like all organisms, tomatoes make more offspring than can survive in nature.

和所有生物一样，西红柿在自然界中殖的后数量超过了它的生存能力。

Only those rats given the saline sired offspring.

只有那些注射了生理盐水的老鼠能殖后。

The Penguins migrate to the frozen sea ice every year to breed and raise their young.

企鹅每年都会迁移到结冰的海冰上殖和养育后。

By 1511, every ship leaving the Americas for Spain was ordered to bring back five breeding pairs.

到1511年，每艘离开美洲前往西班牙的船只都被命令带回五对可以殖后的火鸡。

At best, their dietary rigidity could limit their ability to reproduce or to care for their young.

即便作最乐观的估计，它们这种僵化的食谱也会限制它们的殖能力或扶养后的能力。

And he'll spend the next three years on the sea before eventually returning to breed as a breeding adult.

他将在海上度过接下来的三年，最终以成年海鹦殖后的身份返回陆地。

Unlike most other kinds of fish, they are not able to reproduce for several years, and also produce fewer young.

与大数其他种类的鱼不同，它们在数年内都无法殖，而且后也少。

So we're talking about core tenants of Darwin's theory and more offspring are always produced for a species than can survive.

所以我们在谈论达尔文理论的核心宗旨以及殖的后总是比能够生存下来的后。

If you put in a lot of parental care, then you don't have the resources to make lots and lots of babies.

如果在抚养方面投入太，那用来殖大量后的精力就会不足。

One of the core tenets of Darwin's theory is that more offspring are always produced for a species than can possibly survive.

殖的后余能生存下来的后。

They produced young generally by laying eggs.

它们通常通过产卵来殖后。

As long as two animals are the same species, they can have babies together.

只要两种动物属于同一物种，它们就可以一起殖后。

So, is it possible for two different looking animals to have babies?

所以，两种看起来不同的动物能否殖后？