Invasive Species in the Great Lake

By: David Schaper
Link:http://www.npr.org/templates/story/story.php?storyId=92309879

Summary:
     This article explains about how the water in the great lakes is getting clearer.  This isn't really better.  This means the zebra mussels are taking all the food which is why the lakes are getting clearer.  Now there is a new invasive mussel that is over shadowing the zebra clams.  Fishermen are having a problem with this because all the fish they find are small and there is so much less fish around.  Another invasive species was also found.  It's a disease called viral hemorrhagic septicemia.  It kills the fish in the lake which makes finding fish even harder.  These people are going to try to get congress to pass laws o invasive species.


Opinion:
      I was really suprised about how the bad the great lakes fish can get because of these species that take over the food chain.  I feel like that the old species should be able to adapt to these new conditions.  I also didn't know that a disease could be an invasive species.  I never considered that a disease could count as a species.  


Thoughtful Questions:
1.  How could the fish in the lakes be saved?
2.  What could've brought these invasive species in?
3.  How could we stop invasive species from invading?
4.  Why would Fishermen have a problem with invasive species in the lake?

Are humans still evolving by Darwin's natural selection?
By Olly Bootle
URL: http://www.bbc.co.uk/news/science-environment-12535647

Summary:
This article posted on the BBC's website questions whether or not humans are still evolving. After all, does natural selection even apply to us anymore? Technology and medicine have advanced to a point at which humans are no longer dying of predation, diseases, or starvation at the normal rate. How would we possibly be evolving if we are no longer dying fast enough to let "superior" traits become more common? Studies are showing that, even though we no longer die off at large rates because of "genetic inferiority" we are still evolving. Simple things, such as lactose intolerance, are ways the we progress as a species. What is startlingly revealed is that, now that humans actually have a choice whether or not to reproduce, and some people aren't reproducing, we may eliminate or genes by choice. It appears that natural selection has been replaced with conscious selection. Other studies mentioned say that we are getting shorter and heavier, though the causes are currently unknown. Also mentioned was the fact that humans may start evolving with culture. Our era as a global apex predator species has come to a critical point where the rules of evolution have not changed but have been warped.


Opinion/Reflection:
I find it amazing that, even in our age of basically not dying before learning to talk well, we have managed to keep evolving. We are able to change to fit artificial situations that we ourselves have created. We not only adapted to our primal situation by finding and farming edible plants as an emerging species, we have come to a point where we choose who lives, dies, or is even born. I suspect that humans will become the target of passive, non-invasive evolutionary studies, because we will be able to better understand how species develop in stable environments specifically tailored to them. We should test this with other species, non-endangered ones, to see how they evolve in an environment that is suited to them.

 Thoughtful Questions:

1.What is in our genes that allows us to evolve without severe population drops?
2.Would observations on other species put into similar situations be "wrong," even considering the scientific data it could provide us might be invaluable?
3.Should everyone be forced to pass on genes? Why or why not?
4.What effects do you think mass produced chemicals and substances have on our evolution?
5. Why isn't this question a better joke?

Endangered Species: Humans Might Have Faced Extinction 1 Million Years Ago

Author: Carina Storrs

Publication Date: January 20, 2010

Link: http://www.scientificamerican.com/article.cfm?id=early-human-population-size-genetic-diversity

Summary: A series of genetic studies tell that the human species a million years ago was on the brink of extinction. At the time, the population did not exceed a mere 55,500. Originally, one might assume the population would expand, due to fossils showing evidence of immigration across Africa, Asia, and Europe at the time. But genetic studies show that the population, and its genetic diversity, actually suffered a great deal. Tests were run on human genomes to estimate an effective population size, and compare their genetic diversity with that of the early humans. The effective population of the early humans researchers had estimated (18,500) shows that their genetic diversity is between 1.7 and 2.9 times greater than humans today. The effective population today is about 10,000. Researchers believe the population today is so much greater due to a “population explosion” 10,000 year ago caused by development of agriculture. In conclusion, the genetic “bottleneck” that happened one million years ago was hypothesized to be caused by a catastrophic event, such as a supervolcano.

Opinion/Reflection: I think it is incredible that the result of one natural disaster, if large enough, can almost completely annihilate an entire species. And to think that it was our species is a little scary in it of itself. Clearly though, it did not.  Thanks to the genetic diversity in the early humans, and the human population’s ability to restore itself, our species is able to survive and prosper. As we learned in class, high genetic diversity within a population is better, because it increased the chances of survival through changing environmental conditions. Let’s hope our species can maintain its current level of diversity.

Questions:

1.       What can cause a decline in the genetic diversity of a population?

2.       What can increase it?

3.       Should we try to control our genetic diversity (by ways of genetic experimentation, or otherwise)?

4.       How man licks does it take to get to the tootsie roll center of a tootsie pop?

5.       What kind of environmental changes could cause a decline in population, or a struggle to survive?