7
votes
1answer
223 views

Why are some berries poisonous?

In my understanding, the evolutional function of berries is to be eaten and pood out somewhere else, so that the seeds of the plant spread. Is this so? Then why are some berries poisonous?
9
votes
1answer
235 views

How does population stability evolve?

The number of individuals constituting a population is called population size. Over time population size does not remain constant, it fluctuates to different extent over generations because of ...