The title of this article is base clickbait...
Six-Legged Giant Finds Secret Hideaway, Hides for 80 Years (2012)
11–20 of 97 posts
Re: Six-Legged Giant Finds Secret Hideaway, Hides for 80 Years (2012)
#12What I don't fully understand is, usually when scientists try to preserve rare species, there is a critical mass under which there isn't enough genetic diversity to preserve the species (I've seen ~30 quoted for some rare mammals). But in this case, just two individuals were able to start a viable population. Why are these insects different? I can only think of a couple reasons... - since these insects have a r-selec…
The article touches on this a little bit, I think. Eve's eggs were harvested, incubated (though it turns out only the first 30 were fertile) and became the foundation of the zoo's new population of walking sticks. I am not a real biologist, but I suspect it is some combination of the factors you suggest and that their genome may be simple enough that most defects make the eggs nonviable.
Insects also have complex genomes. The egg fertility most likely has to do with other issues (differences between the natural habitat and captivity, maybe there is a natural tendency for not all eggs to be fertile, etc)
Re: Six-Legged Giant Finds Secret Hideaway, Hides for 80 Years (2012)
#13Alberta is rat free, and is kept that way. Its been rat free for over 50 years now. The border is patrolled to keep the rats out, and there is a hefty $5000 fine for keeping rats.
Questionable. Rat populations have been found at the Medicine Hat landfill, first in 2012 and again in 2014[1]. I guess it's a good sign that it makes national news when a population is found, but they're almost certainly present elsewhere. [1] http://www.cbc.ca/news/canada/calgary/several-rats-spotted-a...
Perhaps, it is better to say "largely rat free." I grew up in eastern Alberta, and I certainly never saw a rat until I moved out of province as an adult.
Re: Six-Legged Giant Finds Secret Hideaway, Hides for 80 Years (2012)
#14What I don't fully understand is, usually when scientists try to preserve rare species, there is a critical mass under which there isn't enough genetic diversity to preserve the species (I've seen ~30 quoted for some rare mammals). But in this case, just two individuals were able to start a viable population. Why are these insects different? I can only think of a couple reasons... - since these insects have a r-selec…
IANARB, but-
Minimum viable genetic diversity is not a particularly well-established or even objectively knowable metric. I think the relevant number is often vastly overstated, or at least stated without mentioning the strong and arbitrary assumptions that need to be made in determining it.
Wikipedia says: "The cheetah has unusually low genetic variability. This is accompanied by a very low sperm count, motility, and deformed flagella.[14] Skin grafts between unrelated cheetahs illustrate the former point, in that there is no rejection of the donor skin. It is thought that the species went through a prolonged period of inbreeding following a genetic bottleneck during the last ice age. This suggests that genetic monomorphism did not prevent the cheetah from flourishing across two continents for thousands of years.[15]"
Now - cheetahs are objectively less fit than they would have been without these population bottlenecks, but they're fit enough that they have not been outcompeted. They are probably highly vulnerable to contagion, though - maybe it's only a matter of time before something figures out how to wipe them out... but maybe not. Science isn't gonna be able to predict that one for you.
Anything we can figure out how to breed in captivity, in a controlled environment without predators and with an abundant food supply, has very low pressure on it - these bugs could all have the insect equivalent of mental retardation and missing limbs and at least some of them could probably make it to successfully reproduce.
Re: Six-Legged Giant Finds Secret Hideaway, Hides for 80 Years (2012)
#15What I find interesting about the paper[1], regarding housing:
> "[include] a jar of water. There is no need to cover the top of the jar, as LHISIs generally do not drown themselves as other insects do, except for very small nymphs on very rare occasions."
So I guess being stuck on a rock surrounded by water taught them to avoid falling into the water, unlike apparently other (land-based) insects.
Re: Six-Legged Giant Finds Secret Hideaway, Hides for 80 Years (2012)
#16The title of this article is base clickbait...
I can't exactly describe how, but it doesn't feel like clickbait. Maybe because it wasn't misleading, obviously it wasn't going to be about real six-legged giant, so I assumed it was an animal or something.
Re: Six-Legged Giant Finds Secret Hideaway, Hides for 80 Years (2012)
#17What I don't fully understand is, usually when scientists try to preserve rare species, there is a critical mass under which there isn't enough genetic diversity to preserve the species (I've seen ~30 quoted for some rare mammals). But in this case, just two individuals were able to start a viable population. Why are these insects different? I can only think of a couple reasons... - since these insects have a r-selec…
IANARB, but- Minimum viable genetic diversity is not a particularly well-established or even objectively knowable metric. I think the relevant number is often vastly overstated, or at least stated without mentioning the strong and arbitrary assumptions that need to be made in determining it. Wikipedia says: "The cheetah has unusually low genetic variability. This is accompanied by a very low sperm count, motility, an…
what is the RB in your "I am not a..." ?
Re: Six-Legged Giant Finds Secret Hideaway, Hides for 80 Years (2012)
#18Earlier quoted context omitted.
IANARB, but- Minimum viable genetic diversity is not a particularly well-established or even objectively knowable metric. I think the relevant number is often vastly overstated, or at least stated without mentioning the strong and arbitrary assumptions that need to be made in determining it. Wikipedia says: "The cheetah has unusually low genetic variability. This is accompanied by a very low sperm count, motility, an…
what is the RB in your "I am not a..." ?
'Real Biologist', as requested by the parent.
Re: Six-Legged Giant Finds Secret Hideaway, Hides for 80 Years (2012)
#19Are there any updates to this story? How is the de-ratification going? A few searches did not turn up anything that seemed like a useful update.
Re: Six-Legged Giant Finds Secret Hideaway, Hides for 80 Years (2012)
#20Earlier quoted context omitted.
Questionable. Rat populations have been found at the Medicine Hat landfill, first in 2012 and again in 2014[1]. I guess it's a good sign that it makes national news when a population is found, but they're almost certainly present elsewhere. [1] http://www.cbc.ca/news/canada/calgary/several-rats-spotted-a...
Perhaps, it is better to say "largely rat free." I grew up in eastern Alberta, and I certainly never saw a rat until I moved out of province as an adult.
I mean, I grew up in California, not even remotely rat free, and I think I've seen... three-ish... rats in my nearly 40 years? Besides pets or lab animals.
Rats hide. Doesn't mean there aren't a fairly large number of them around.