How are new species formed?

Speciation is pretty much evolution in action, two species emerge from a single one. Because they share gene pools they have similar genes.


This pretty much works from the fact that new species can only form from pre-existing species. The idea is that a group of organisms from the space species can become separated geographically so they can't reproduce, this is called geographical isolation. When the two groups are completely separated, the two areas can have different environments. Like in every habitat there are some individuals which are better adapted to compete. These are more likely to survive and reproduce, this means the alleles (genes they have) are more likely to be passed onto their offspring. This means that over many generations the allele frequency increases so the individuals are better adapted to live in that environment. Eventually, the alleles present in one group 'evolve' and can become completely different to how they were initially. Because they might be completely different they won't be able to interbreed to produce fertile offspring, so they're now no longer the same species. 


Definitions


Species: A group of organisms which can interbreed to produce fertile offspring, they also share a gene pool.

Lemurs!

Lemurs are amazing creatures but they're also endangered. Scientists have discovered an incredible evolutionary past - suggesting Lemurs where once as big as some gorillas! They're also incredibly sociable, perhaps because their family can be as big as 15. Of course, because of their endangered status, we want to do everything we can to protect them - that's why we see them in many of our zoos - in fact, in zoos they can live up to 30 years, compared to the 18 years they can live up to in the wild. When it comes to dominance, it's all girl power! Scientists think that this is an evolutionary tactic for the females as they need more resources to give birth and look after their young. They also use their scent as a huge power advantage. They get involved in "stink fights", where they rub their tails against the tree as a huge warning to the other lemurs!

How do gorillas raised in captivity know what's safe to eat in the wild?

By instinct. Similar to how we have evolved to enjoy the taste of the safe foods and dislike the poisonous ones, gorillas have done just the same. In the wild mountain gorillas eat leaves,shoots and stems so much so an adult male can chomp through a massive 18kg of vegetation in a day. In experiments gorillas were given over 2000 pairs of foods and they then had to choose between them. Throughout the experiments they demonstrated consistent food choices in high sugar fruits with a high ratio of sugar to fibre, this is even the same using pictures of the fruit!