Could global warming help species?

I was reading today how there are more species in the tropics than anywhere else in the world. One theory suggests that evolution happens faster in the tropics because tropical conditions increase the mutation rate, and thus the amount of genetic variation available for natural selection.

So, my question, could global warming actually lead to more species inhabiting the earth by making the rest of the planet warmer?

[Jeremy]

The big ecological theory as to why the tropics contain more biological diversity is kind of interesting. I will sum it up here but we can always expand it later.

You have to first know about climate change. Areas closer to and at the poles have more radical changes during different climate change eras throughout the world's history. These radical variances make it hard for certain species to evolve and establish niches. Thus, you have a higher species extinction rate.

The tropics generally have lower climate flucuations and species can easily adapt because the changes are less severe. These species can also evolve and establish niches and create a richer area of biodiversity.

Then, of course, there are cosmopolitan species that have learned to adapt in any environment and can be found in tropic, temperate, and even sub arctic/antarctic regions.

To answer your question, there is always going to be a debate and I don't think anyone really knows the answer. But think about 4 things:

1) Is the climate changing too fast to allow species to adapt to the new climate? For example, coral bleaching.

2) Look at the temperate species that are at risk of extinction (salmon, polar bears, just to name 2) and ask would it be worth it?

3) Would we be gaining new species or just having larger ranges of already existing species?

4) Evolution of new species (or spreading of tropical species) would happen so slow that we would not see it in our lifetime.

Jeremy

[bruce]

Nearly a third of the species on Earth will be at risk of extinction if mankind fails to stop the rise in greenhouse gas emissions, a major UN report will say this week.

http://www.telegraph.co.uk/earth/mai.../eaipcc112.xml

Apparently not

[nickupton]

This may possibly be true if the earth was full of unbroken habitat, but what remains is so fragmented that how would these species move on?

Those species that depend on cooler climates would have nowhere to go at all.

[forfi]

Originally Posted by nickupton

Those species that depend on cooler climates would have nowhere to go at all.

Same place as the ones who depend on warmer climes went during the ice ages?

[nickupton]

Same place as the ones who depend on warmer climes went during the ice ages?

Towards the equator?

[forfi]

Originally Posted by nickupton

Towards the equator?

Snowball Earth?

Extinction is a fate that awaits all species,exciting times ahead.

[Aracari]

Warmer or colder is not what really matters... the most important thing is how this subtle changes in temperature can affect the rainfall.

Warmer in the tropics would usually mean less sustained rainfall and thus drier conditions. This would be fatal for a huge number of species but beneficial for a few others that are adapted to dry conditions.

[Skeptic]

Life is more versatile than we usually give it credit for. The world has been through heaps of major changes in the past, and still burgeons with life.

Take the coral bleaching thing. I am a keen scuba diver, and have dived in tropical, sub tropical, temperate and sub antarctic waters. There is an enormous overlap between ecological zones. Reef building corals flourish in the tropics, but are found in smaller numbers in sub tropical waters. If the world warms enough, it is entirely predictable that abundant coral reef communities will develop in what is now subtropical areas.

[Aracari]

I don't think it's that simple. Temperature shifts would change ocean currents too. Corals might grow better in some other areas though.

The problem is that we, as humans, are used to this weather/ecological condition. Changes right now would mean horrible results all over the world.

Changes in the past have been much slower, a transition was easier.