I read an interesting article on the peculiar ability of larvae of sea floor species called sand dollars. Apparently they are able to clone themselves into two smaller copies when faced with possible danger, like the presence of fish mucus on the sea floor. Since a number of species of fish eat the larvae of sand dollars, they adapt to the situation by cloning themselves into two when fish mucus is detected in their vicinity. The term cloning, while technically correct, might come across as something of a misnomer here, since the actual mechanism relies on the original splitting into two smaller yet genetically identical versions of the original. Think of starfish and how they are able to regenerate into whole forms when cut into smaller pieces, as each of those pieces slowly grow into a whole starfish. According to the article linked above the sand dollars are biological cousins of starfish so the precise method of the ‘cloning’ itself isn’t as mysterious as it would first appear. After all, most of us have seen or are at least familiar with the variety of plant and animal species that are known for their regenerative capabilities.
What makes this species appeal to me, however, is that external trauma is unnecessary for this macroscopic and relatively complex organism to split into two identical copies of itself. Starfishes and plants need the environment to actively interfere for their regenerative mechanism to activate. However, these sand dollars seem to be able to demonstrate such behavior at will, or at least evolved in such a way that they are able to actively split and clone themselves in presence of certain chemical stimuli in the environment, with no need for physical injury. With the practice and study of synthetic biology becoming increasingly wide spread and accessible, such novel biological behavior might suggest wide variety of future utility of the specific protein/genomic mechanism behind the organism, medical, industrial, and perhaps even architectural. With the study into cloning being such a specialized discipline it is, such macroscopic and controllably ‘splitting’ organism will be able to open worlds of opportunities for those who wish to study mechanics and effects of cloning. Being able to observe self-cloning at the scales of bacterium is one thing, observing and possibly controlling them at macroscopic scale is another. With the chemical stimuli in the environment as the primary factor for the organism’s decision to split, it would be a relatively simple matter to control such biological construct as we see fit, provided that we are able to engineer the organism from ground-up.
There are other, perhaps even more far-reaching subjects that might be studied using this organism. The behavioral pattern of cloned organisms in comparison to their original, for example. The precise method at which random variables of the biological evolution was able to give birth to such mechanism of selective self-cloning is very interesting to me as well. Was it really ‘random’, or was there some sort of chemical or environmental preferences that lead to such evolutionary marvel? How about the problem of identity? Can such concept be manifest at some level in rather dense organism like the sand dollars? If so, how would they cope with the moments of their ‘split?’ Or are they simple biological machines feeding, expelling, and propagating without apparent ‘will?’ (whatever ‘will’ might be. On this point Lynn Margulis might have suggested that will as an expression of life form might not require complex nervous systems like that in humans) I am anxiously waiting for any follow-up study of the organism.