Friday Randomness (Life edition)

It's Friday again, so here's some interesting science stuff to get you through the weekend:

The ten most bizarre theories about why the dinosaurs went extinct - the comet theory is the one you know, but these are a bit more complicated.

Are you afraid of the right animals?

Spider bites are missing for a reason: Nobody in the U.S. has died from a black widow bite in the last 10 years

There's been a lot of work recently on stem cell research, and for good reason! Stem Cells are the special cells that can change into whatever is needed, the first cells that are produced when a fetus is growing. For the first time, scientists have grown working cartilage from stem cells.

Speaking of working from the genetic level, scientists have used gene therapy to cure deafness!

And finally, a very cool video about how the re-introduction of wolves into the Yellowstone National Park actually changed the flow of rivers in the area, in addition to revitalizing the entire ecosystem:

Who knew that a predator could make a difference?