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Help/share opinion please?

This is a complicated question that I am having trouble understanding,

What is your opinion on this question?

Experts estimate that human activities cause the extinction of hundreds or thousands of species every year. The natural rate of extinction is thought to be a few species per year. As we continue to alter the global environment, especially by cutting down tropical rainforests, the resulting extinction will probably rival that at the end of the Cretaceous period. Most biologists are alarmed at this prospect. What are some reasons for their concern? Considering that life has endured numerous mass extinctions and has always bounced back, how is this present mass extinction different? What might be some consequences for the surviving species?

I guess, can someone explain what the Cretaceous Period please? I have no idea what that is...

Biology question.

Thanks, 10 points promised to whoever helps me!

Thank you!

2 Answers

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  • 9 years ago
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    Cretaceous Period is when all the dinosaurs went extinct- current evidence is suggesting meteor.

    Things that are alarming about it are:

    This is not a "natural" extinction process- it can be controlled but isn't.

    We are losing species that can help humans- ie possible cancer drugs.

    We don't understand ecology as much as we want to and any study would suffer from inconsistent evidence due to "oh god my study species was a keystone species and is now extinct" (keystone species (such as sea stars, otters and possibly wolves) control diversity of species in a ecosystem by lowering number of competitively dominant species).

    Lots of mutualisms exist and a loss of one of those species would eliminate or or more other species. Ants + host plants or plants + pollinators.

    Some of the changes are so rapid that mutations don't have time to occur to allow for evolution of a population to occur.

    Surviving species may not have the needed resources, such as parasites need specific organisms for hosts.

    Also humans are not immune to this mess- we kill off all our food we go extinct too. It is just a matter of time. We use coal to regulate our environments what happens when we turn the world to desert and run out of coal.

  • 9 years ago

    Cretacius period occurred after the Jurassic period and is when all the Dinosaurs died out (mass extinction event). The surviving species need to interact with each other for food and resources, with less surviving species, there will be less resources. If we kill a particular set of plants which an insect feeds on then the insect will die out then the birds that feed off the insect will die out, if they die out so do the predators that feed on the birds etc. The surving species will not have as many resources or food due to a reduction in biodiversity.

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