Brave New World

When considering hybridization it is important to note that the biological species definition refers to the potential to interbreed in nature. This specifically excludes whatever technologies we may develop to allow such hybridization in the laboratory. The few cases of animal hybridization observed in the wild (see last posting for links to two insect examples) are interesting partly because they are so unusual.

The accompanying photograph of a frog and mouse is classic tabloid bait and switch. The mouse is trying to avoid a flood - check out the link, apparently it is a real, unstaged photograph from flooding in India. There are no frog/mouse hybrids in nature - think of all the potential isolating mechanisms.

But it seems to be human nature that we are fascinated by the potential of hybridization - from the mythical Chimera, with a lion's body a serpent's tail and a goat's head to the pot-bellied elephant in Southpark. If we move from nature into the laboratory then we can circumvent a great number of the potential isolating mechanisms and it seems that much is possible.

Here are some recent news articles. These are generally not true hybrids as we have been talking about them but I'm including them here to show just what is now possible in combining organisms in the laboratory. The one thing they have in common for me is that my response is invariably the same. First shock at what is now possible, then an understanding of the potential benefits, and finally sadness at realizing that with the potential shock value of newspaper headlines much of this research may be in serious peril.

1) Mice have been used to produce viable monkey sperm using tissue transplanted from the testes of macaques. The work may be very useful in helping conserve endangered species on the brink of extinction. It might also be possible to grow human sperm in mice, although the team agree this would be a controversial move. An experiment that would raise concerns is genetically engineering mice to produce human sperm and eggs, then doing in vitro fertilization to produce a child whose parents are a pair of mice.

2) At Stanford University in California an experiment might be done later this year to create mice with human brains. They have already created mice with brains that are about one percent human and later this year will conduct another experiment where the mice have 100 percent human brain. Before being born, the mice would be killed and dissected to see if the architecture of a human brain had formed. Weissman said he's not a mad scientist trying to create a human in an animal body. He hopes the experiment leads to a better understanding of how the brain works, which would be useful in treating diseases like Alzheimer's or Parkinson's disease.