The Daphnia, or water flea,
Scientists have studied Daphnia for centuries because of its importance in aquatic food webs and for its transformational responses to environmental stress. Predators signal some of the animals to produce exaggerated spines, neck-teeth or helmets in self-defense. And like the virgin nymph of Greek mythology that shares its name, Daphnia thrives in the absence of males — by clonal reproduction, until harsh environmental conditions favor the benefits of sex.
Arguably, more is known about the ecology and stress biology of the water flea than any other animal. The genome project was conceived with an expectation that many new gene functions would be uncovered when studied in light of the animal’s natural environment — not necessarily expecting to discover many more genes.
Yet, Daphnia’s genome is no ordinary genome.
“Daphnia’s high gene number is largely because its genes are multiplying, by creating copies at a higher rate than other species,” said project leader and CGB genomics director John Colbourne. “We estimate a rate that is three times greater than those of other invertebrates and 30 percent greater than that of human.”
“One theory is that Daphnia is so good at adapting to so many environments because it has this huge catalog of genes to call upon,” says Thomas. The researchers note that more than one-third of Daphnia’s genes are undocumented in any other organism – they are completely new to science.
Daphnia, as I understand it, have been used as a barometer of lake condition, because they are so sensitive to conditions, and so quick to adapt (across generations, not within). The combination of an environmentally sensitive species well studied as an ecoresponsive indicator, and a thorough understanding of the underlying genetics, will allow an unprecedented depth of understanding in examining epigenetic processes.
Or, maybe I misunderstood everything.
An update, of sorts. I just saw this really nice pdf file of my verse. Apparently, I’m listed on the Daphnia Genomics Consortium Collaboration Wiki… and apparently, somebody made a really nice pdf of my verse without asking (tsk, tsk!).
weirdbuglady says
How cool! Daphnia are fascinating in their biology as well as being quite adorable. I often get requests to make them as plushies (got a few in the shop now). I really enjoy finding them in the wild, watching them 'jump' through the water with their antennae.
Theophylact says
And this is why Jains and Orthodox Jews never swim…
Anonymous says
How many chromsomes do they have?
Cuttlefish says
They have 12 chromosomes.