Science

[Insidious Rex]

Originally Posted by sisterandcousinandaunt

No, cute is the otter's stock in trade. Without "cute" they're rapacious carnivorous members of the weasel family with promiscuious lifestyles.

Well Ive been called worse.

[Nerdanel]

A completely female species

A species of ant consisting only of females has been found. This is interesting both because this causes clonal colonies of ants and because usually, unfertilised ants only are able to produce males: in Hymenoptera (e.g. ants, bees and wasps) females are produced from fertilised eggs (and are thus diploid) whereas males are produced from unfertilised eggs (ie. they're haploid - this also means males have no sons or fathers). The species in question is both able to produce diploid, unfertilised eggs that develop into females and is apparently not producing any males at all. This is quite an amazing alternative evolutionary path.

Mycocepurus smithii is a fungus-growing ant whose range is from Mexico to the Caribbean and Argentina. They grow a clonal fungus for food and in exchange, the fungus is spread by the ants to new colonies: when new queens are produced and leave their maternal nest, they take a piece of the fungus in their mandibles, which they then use when they're establishing their own colony. The ants also keep their fungus clone pure. This symbiosis has been readily studied in many ants. Similar symbioses exist between some termites and fungi - ants and termites are very distant relatives and these similar symbioses have evolved independently from each other.


Mycocepurus smithii in its fungus garden.

The researchers used several sources and experiments to conclude that M. smithii most probably is an ant species which completely lacks males. First, they noticed that when held in laboratory conditions, colonies of M. smithii didn't produce any males, but did produce queens and workers (which both are female). The 30 other species of closely related ants were held in the same lab and all produced males as well as females. Unmated females of the species were also observed to produce offspring, but only females (note again that in other ant species, unmated queens can only produce haploid eggs that develop into males).
Second, genotyping of 12 colonies of M. smithii showed that the genotypes of the queen and all her offspring was identical, pointing to clonal (asexual) reproduction.
Last, the reproductive organs of the M. smithii queens were degenerated. A structure that the male reproductive organs lock into during mating were missing and no spermatheka (spermfilled sacs in the female - in ants, the queens mate during one mating flight, after which they store the sperm they get hold of until they die, in many species up to 20 years) were found in any of the queens taken from natural colonies.

M. smithii presents a very interesting case for many reasons. For example, asexuality is often associated with greater susceptibility to disease due to the lack of variation in disease resistance (if one gets infected, all can theoretically be infected) and with evolutionary disadvantage due to the slow production of new genotypes. The case is also interesting because of the changes it brings to traditional parent-offspring conflicts that are very much present in sexual ant species (and other eusocial insect societies).

Source: Himler et al. 2009. No sex in fungus-farming ants or their crops. Proceedings of the Royal Society B. Published online 15 April 2009.
doi: 10.1098/rspb.2009.0313

(the abstract of the article: http://rspb.royalsocietypublishing.o....0313.abstract)

[inked]

Very interesting. And they could be geographicalised as Amazonian, too.

[GrayMouser]

Foretelling?

http://en.wikipedia.org/wiki/Consider_Her_Ways

[Nerdanel]

Originally Posted by GrayMouser

Foretelling?

http://en.wikipedia.org/wiki/Consider_Her_Ways

nice!

[GrayMouser]

And while we're feeling antsy:

Humans aren't the only species that have had to deal with the issue of slavery. Some species of ants also abduct the young of others, forcing them into labouring for their new masters. These slave-making ants, like Protomagnathus americanus conduct violent raids on the nests of other species, killing all the adults and larva-napping the brood.

When these youngsters mature, they take on the odour of their abductors and become the servants of the enslaving queen. They take over the jobs of maintaining the colony and caring for its larvae even though they are from another species; they even take part in raids themselves. But like all slave-traders, P.americanus faces rebellions.

Some of its victims (ants from the genus Temnothorax) strike back with murderous larvae. Alexandra Achenbach and Susanne Foitzik from Ludwig Maximillians Universty in Munich found that some of the kidnapped workers don't bow to the whims of their new queen. Once they have matured, they start killing the pupae of their captors, destroying as many as two-thirds of the colony's brood.


Ants that are targeted by slave-makers take massive hits to their colonies and they are under intense pressure to resist these marauders. But all the defences discovered so far happen before the raids have been successfully completed. They involve better fighting skills, quicker reaction times when enemies are spotted, hastier escapes and so on.

Some scientists have suggested that strategies like this would be impossible to develop because the enslaved workers are caught in an evolutionary trap. Far away from their own colony, and sterile themselves, there is no way for them to increase their reproductive success. But Achenbach and Foitzik have rejected this idea - their conclusion is that by conducting assassinations within their new home, they severely reduce the slave-makers' numbers and their ability to conduct raids. That safeguards the future of their relatives.

Achenbach and Foitzik collected 88 colonies of the slave-making P.americanus ant that had abducted workers from three species of Temnothorax. They found that the workers clearly care for the larvae, and nearly all of them were raised until their pupated. But at that point, the slaves' behaviour changed dramatically, taking on a more homicidal bent.

Two-thirds of pupae died before they hatched. The mortality rate was even higher (83%) for pupae containing queens, but very low (3%) for those containing males. The duo saw that the captives were deliberately killing the healthy pupae. In about 30% of cases, as in the photo, the workers would gang up to literally pull the developing ants apart. Another 53% of the pupae were killed by neglect, by workers who moved them out of the nest chamber.

http://scienceblogs.com/notrocketsci...ant_slaves.php

"I am Spartacus!" "No, I am Spartacus!" No, I am ....." x 500,000.


From Scienceblogs; highly recommended.

http://scienceblogs.com/

[inked]

Oops, there goes another rubber-tree plant!

http://www.youtube.com/watch?v=cSIy4W83DqE

[inked]

That Artic ice is just not declining like Al Gore wants it to!

The real science (from Canada even!)

http://ice-glaces.ec.gc.ca/content_c...Extent_eng.PDF

stuff ain't going away!

[Earniel]

That's three seperate threads now you're posting in about Gore, Inked. It's starting to look an aweful lot like spamming. Keep your global warming links in one thread from now on, please.

[inked]

Sorry, Earniel, it's just that Copenhagen thingy and reality don't meet. No intention of spamming.

[inked]

TOP TEN BIOETHICS CONCERNS ... "As we come to the end of the first tenth of the 21st century, pundits are making lists about the decade just past: the biggest stories, the worst movies. In that spirit, here’s a list of the top ten stories in bioethics.

This isn’t an idle exercise. Bioethics matters. The field exerts tremendous influence over the most important questions of public policy and moral values: How should we treat the most vulnerable and dependent among us? What makes us human? Indeed, is it even morally relevant that one is human? Trends in bioethics, thus, illuminate where we are as a society and the nature of the culture we are creating for our progeny."

http://article.nationalreview.com/pr...E5ZDEyOGU4Mzk=

[GrayMouser]

Nobel goes to developer of IVF in humans.... a little surprising, given that it's very applied, not basic stuff.
http://www.csmonitor.com/USA/Society...ies-behind-IVF

[inked]

"It has been an incredibly controversial research from the beginning. Despite the incredible promises it offers, it's also raised significant bioethical issues that divide many people in society," says Nita Farahany, a philosophy professor at Vanderbilt University in Nashville, Tenn., and a member of the Presidential Commission for the Study of Bioethical Issues. IVF "could raise issues that may be relevant to the work of the commission," she adds. [Editor's note: The last sentence and quote in this paragraph were revised to better reflect Ms. Farahany's overall comments.]

Edwards's Nobel is a nod to a clinical achievement with an appreciable and personal impact on the families of IVF babies. But what such babies will look like in the future may also help define Edwards's ultimate legacy.

Says Mr. Caplan of the University of Pennsylvania: "If you hold up a baby that was begun in a dish and designed through genetic engineering, which is taller, smarter, and healthier than its parents, will people still smile?"

op cit

[Grey_Wolf]

They might just be a tad abhorred.

[Grey_Wolf]

On another matter -

What do you think of laser-induced fission of the Carbon and Oxygen in the unhealthy combination it presents in CarbonDioxide?

This process would force apart the Carbon, which will, I suppose, turn into powder or something, and the Oxygen, which can be easily stored in tanks.

Glad to have your views on the matter.

[Jonathan]

Originally Posted by Grey_Wolf

What do you think of laser-induced fission of the Carbon and Oxygen in the unhealthy combination it presents in CarbonDioxide.

I remember you looked for feedback on a similar idea in the Global Warming thread. See my reply there as well

While laser fission might be feasible on a very small scale, it sounds like it would require a lot of energy per CO2 molecule. Enzymatic cleavage of CO2 would probably be more efficient (as the very nature of enzymes is to lower the energy needed for a chemical reaction to take place). But I dare say the most cost-effective strategy would be to just bind or capture the CO2 in a way that separates it from the atmosphere.

[GrayMouser]

Yea, bioengineering will be one of the big concerns of the 21st c.

If you were a parent who was a carrier of Huntingdon's or Tay-Sach's disease and you could prevent your future child from inheriting it through genetic manipulation, wouldn't you do it?

But then of course comes the problem of 'improvement'. How about dwarfism? But then how tall is tall enough?- after all, 'heightism' is probably the most wide-spread form of discrimination in the world- shouldn't your child get that advantage?

"O Brave New World" indeed.

[inked]

Speaking of that, are these "lies, damn lies, or statistics" (apologies to Mark Twain)? http://www.breitbart.com/article.php...show_article=1

Two decades (plus) ago when I was in medical school, the claim was for 10% of the population?

What has happened?

[Tessar]

The problem with any statistic like that is that it's personal report. If someone walked up to me on the street and asked me to fill out something like that, I would not admit to being homosexual regardless of whether it was anonymous. For that matter, if people come right out and ask me in person I don't admit to it. If they want to somehow go digging through my past and they find out about it on their own that's their problem, but I don't just tell them.

I can think of two other people I know, who are atheists and in relationships, who do the same thing.

[Gwaimir Windgem]

Yeah, it's pretty widely acknowledged that there is significant difference between those who are predominantly or significantly same-sex attracted and those who will identify themselves as such.