Do impacts trigger extinctions? Impact theory still controversial - “The increased interest in meteor impacts will be productive. We’ve seen in the past years people finding many more impact craters,” French says. “This is very exciting business. It’s a totally new wild card mechanism for how Earth changes.”
This image shows a human glial cell (green) among normal mouse glial cells (red). The human cell is larger, sends out more fibers and has more connections than do mouse cells. Mice with this type of human cell implanted in their brains perform better on learning and memory tests than do typical mice.