On death as the mother of beauty, and frog embryos.


Embryo_Deformities“Objects which in themselves we view with pain, we delight to contemplate when reproduced with minute fidelity: such as the forms of the most ignoble animals and of dead bodies. The cause of this again is, that to learn gives the liveliest pleasure, not only to philosophers but to men in general…” — Aristotle, in Poetics (335 B.C.E.)

In a large egg mass of the Wood Frog (Rana sylvatica),  I observed several deformed embryos, each grotesque, beautiful, and captivating to the eye. Most of the frog spawn contained tiny spherical blastulas, each rapidly dividing according to its unique set of genetic instructions, but the deformed individuals took on many disturbing shapes. Perhaps the bane of their development was a single genetic mutation, an error that occurred during recombination that resulted in a gene that did not function the way it should. One tiny glitch in development, and before long the cumulative effects of the change are manifest in a striking departure from the typical Bauplan of the species.

In many cases, the result of such a gene mutation will be something akin to these deformed embryos, an utterly failed organism that will not survive to adulthood, much less transfer its genes to the next generation. In other cases, the mutation will not preclude adult development, but will nevertheless have some strange detrimental effect on the animal (e.g., infertility or deformed limbs); this animal will be out-competed by its neighbors, and the mutation will not persist very long in the population, even if it survives a generation or two.

But every once in a while, on the most fortuitous of occasions, such a mutation will actually cause a change that improves the fitness of the mutant. Perhaps it causes the frog’s webbing to extend all the way to the end of its toe rather than to the first knuckle. Such a slight adjustment might allow it to be a faster swimmer, thus facilitating its survival and reproduction.

It is a wonderful thought:   That which is most abhorrent in Nature provides the raw material for Its evolutionary transformation, and thus Its beauty.

Advertisements
Categories: Evolution, Herpetology, Natural HistoryTags: , , , ,

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: