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Human Actions and the Sixth Mass Extinction

The rise of homo sapiens on various continents coincides with a decline in other large animals.

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What's In A Widow's Color?

What's In A Widow's Color?

Brown Widow (Latrodectus geometricus) the newcomer to North America.

That's A Matter Of Preference

Invasive species are receiving a lot of attention these days, so you've probably heard of them. Usually, invasive species receive a lot of attention after they have a big effect on whatever new ecosystem they have entered, but there are a lot of failed invasions that don't get attention. In fact, sometimes even when it's clear that an invasion is going on, it isn't clear what the outcome will be.

No Duh's and Head Scratchers

If you need help scratching a mental itch, use the resources below:

  1. Where are Brown Widows having great success displacing Black Widows? How does this relate to the areas in which Black Widows evolved? Do you think this relationship may be a factor in the Brown Widow's success? Why or why not?
  2. How could this change in spiders affect humans? Do you think that overall this will be a positive or a negative thing for humans? Be sure to consider different environments and situations.
  3. How do you think this change in spider abundance may effect the ecosystems in Southern California? Are natural ecosystems most likely to be affected? Is it certain what is going to happen? What information would you collect to better understand and manage the situation?
  4. What effect do you think humans have had on the success of the Brown Widow's invasion? How does this situation effect your view of invasive species?


Black Widow (Latrodectus mactans)

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