You might think that it would take genetic engineering - or some Frankenstein-style cutting and pasting - to give a worm the head and brain of another species. You'd be wrong.
Scientists at Tufts University tweaked the cellular signals of flatworms to accomplish just that. They reported their success in a study published on Wednesday in International Journal of Molecular Sciences.
The researchers, led by Tufts professor Michael Levin and undergraduate student Maya Emmons-Bell, cut off the heads of some Girardia dorotocephala - worms known to regenerate with ease. Then they interrupted the electrical pathways that cells inside the worms use to communicate. By doing so, they were able to make the new heads grow into shapes sported by other, closely related worms.
Brains followed suit, taking on the morphology of related worms instead of that typically seen in Girardia dorotocephala. Examples of these new heads are shown in the bottom row of the image to the left.
It's clear that genes aren't everything. Even in humans, environmental factors can change the way the same genes are expressed. In flatworms, it seems, these non-genomic changes can even be manipulated to change brain and body shape - at least temporarily.
