Briefly describe the reasons associated with three mass extinctions recorded in the geologic record. If there are less phyla today than during the Cambrian explosion and if 99% of all species have gone extinct, how can it be that the number of families have increased through time
Briefly describe the reasons associated with three mass extinctions recorded in the geologic record. If there are less phyla today than during the Cambrian explosion and if 99% of all species have gone extinct, how can it be that the number of families have increased through time
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Today you will be using an online visualization tool that illustrates the vulnerability to extinction of different groups of (mostly) terrestrial organisms. Spend some time looking through the website at projects.propublica.org/extinctions.
What group of organisms (mammals, reptiles, amphibians, or birds) hasâ¦
â¦the largest percentage of at-risk species? Whatâs the percentage?
â¦the smallest percentage? Whatâs the percentage?
Select any one family from the mammal, reptile, amphibian, or bird groups that has at least 40% of its species at risk for extinction (that is, the family grouping is colored red) and do some Internet research to identify some major mechanisms that have placed that members of that family at risk (e.g., climate change, habitat destruction, pollution).
Family:
Reasons for at-risk status:
Time for another website. You can google âGuardian endangered species mapâ â the site you want should be one of the top two search results â or you can type in the following: http://www.theguardian.com/environment/interactive/2012/sep/03/extinct-and-endangered-species-interactive. This map shows where species have already gone extinct and where the critically endangered species of today are located.
What country has had the largest number of extinctions since 1500? Within your group, talk about why this might be.
Now go to the âCritically endangered speciesâ view of the map (upper right corner). Where are the spots with high concentrations of critically endangered species? For your answer, you can either list specific countries, continents, sub-continental regions (e.g., southeast Asia, northern Asia), or climatic zones (e.g., tropics, subtropics). Your choice.
Now go to the âIn numbersâ part of the map (upper right corner). By clicking on the circles, you can see which groups of organisms are most threatened in different regions of the planet.
After clicking on all of the regions on the map, can you make generalizations about what group(s) of organisms is/are most threatened globally? (For the purposes of this question, ignore the âplants, insects, and otherâ catchall category and focus on the other groups.)
Are there important regional differences that stood out to you?
