25 October 2011

Celebrate diversity: Absent fathers might not be missing fathers

ResearchBlogging.orgThat you don’t see males around when a female gives birth or lays eggs doesn’t mean that a male wasn’t involved. Females of many species can store sperm for long periods, sometimes their entire lives. Queen honeybees, for instance, go on a single “nuptial flight”, and the the sperm they gain on that flight is enough for the rest of her life, which can be several years.

A rattlesnake (Crotalus adamanteus) is making the news with this point. A female that had been isolated for five years recently had nineteen little snakes. After having been alone for so long, parthenogenesis seemed a possible candidate to explain the happy occasion.

Not so. Genetic tests showed the offspring had genes from another animal besides momma, so this female had mated at some time in the past. How far back? Not known.

All of this means that determining parthenogenesis is trickier than it first appears.

Crayfish can also store sperm (Albaugh 1973), but how long is the upper limit? I’m not sure. So pet owners, just because the lone crayfish you got a while ago had babies doesn’t mean it’s a Marmorkrebs or is reproducing asexually. It may have just been biding its time.

References

Albaugh DW. 1973. A case of long-term sperm retention by a female crayfish (Decapoda, Astacidae). The Southwestern Naturalist 18: 97-98.

Booth W, Schuett GW. 2011. Molecular genetic evidence for alternative reproductive strategies in North American pitvipers (Serpentes, Viperidae): long-term sperm storage and facultative parthenogenesis. Biological Journal of the Linnean Society: In press. http://dx.doi.org/10.1111/j.1095-8312.2011.01782.x

Photo by OZinOH on Flickr; used under a Creative Commons license.

21 October 2011

Coming soon...

20 October 2011

Tracking your colony: SAPling

Where was this when I started my Marmorkrebs colony?

A new article in The Journal of Experimental Biology describes a software package called SAPling that is intended to track the pedigree of entire colonies of asexually reproducing animals. You can find the software at: http://genomics.princeton.edu/schoetzlab/software.html.

I’ve downloaded the software, which is written in Java. I have not quite figured out how to run the program yet, though. There’s no standard *.exe file to run. If anyone knows how to get Java *.class files going, I would be most appreciative of any pointers!

Reference

Thomas MA, Schötz E-M. 2011. SAPling: a Scan-Add-Print barcoding database system to label and track asexual organisms. The Journal of Experimental Biology 214(21): 3518-3523. DOI: 10.1242/jeb.059048

04 October 2011

Going small without going home

Over at the SciFund Challenge blog, I have a guest post about how the current grant proposal system strongly pressures scientists to ask for lots of money, even if the project doesn’t need it.

Big science is a wonderful thing. But we need new ways to fund small science. There are many projects where a few bucks here and there will grease a lot of wheels. We shouldn’t have to have the same level of difficulty in getting, and spending, small pots of money as the big pools of money.

I will be promoting Marmorkrebs research as part of this crowdfuning challenge in November. It will be fun!