- since these insects have a r-selection curve, it's ok if 90% of the offspring are genetic defects, you can always produce another 1,000 eggs
- the insects had maintained such a small population for so long that any critical defects had been bred out
But I'd be interested to hear from a real biologist.
Edit: oops, meant r-selection, not k-selection
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.
"The cheetah has unusually low genetic variability. This is accompanied by a very low sperm count, motility, and deformed flagella. 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."
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.
Section 3.2 (p8)
The population at Melbourne Zoo, being descended from a single pair, appeared to experience increasing symptoms of inbreeding over two generations until four adult males were introduced, descended from a second pair held at Insektus in Sydney, and their genes began to have an influence.
After new males were introduced, no further abnormalities were observed...
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.
As such, I would not expect inbreeding to affect the viability of an insect species at all. If they can produce a viable first generation, the large majority of that generation can produce a viable second generation.
Mammals might have a harder time with inbreeding because they produce few children, and as such any problems are less likely to be resolved through another line.
There's also likely some luck involved that the initial two on that island happened to be viable colony starters.
In the long term, inbreeding is also a problem because it limits genetic diversity, which means anything with an adverse effect on one individual will adversely affect all individuals (the same problem as "monoculture" in software).
> 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)
The Blue Book ("Viable Populations for Conservation") puts it between 50 and 1000 individuals for 95% probability of survival over 100 years, but it's highly variable between species and ecosystems on both intrinsic (r-strategy which you quoted) and historical grounds: for the second case, the Mauritius Kestrel was brought back from an effective population of 2 mated pairs. But its ecosystem has a carrying capacity of under 1000 individuals and it had already gone through several genetic bottlenecks.
The weta are r-strategist anyway, Poor Knights wetas have clutches of 200~300 eggs.
Ill effects of incest can be avoided with https://en.wikipedia.org/wiki/Genetic_purging . In case there are only very few individuals left that's probably not what one wants to do, though.
> "[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.
And strong enough to defeat surface tension.
The question that drives scientists to do what they do.
Rats hide. Doesn't mean there aren't a fairly large number of them around.
EDITED to add: We had cats which killed mice and gophers and birds and voles and all sorts of creatures. I NEVER saw a rat. I know it is hard to believe, but Alberta really is (at least mostly) rat free.
Late in the evening, one would pop up. I could get up to chase it away, but it wouldn't flee until I got close, and it would pop out again a few seconds later. It knew it could out-wait me and there was little I could do to stop it that night. Trying to block the hole merely meant they ate away the wood around the hole, until they could get back in again.
Mice aren't a problem at all. You don't want rats.
I believe I'm not very exceptional a person thus I suspect they'll have difficulties convincing people to have this species reintroduced on any inhabited island.
This "sexism in language" derail is totally irrelevant to the topic and I don't think it does anything to help actual sexism in STEM or anything like that.
I think the issue here is that sexism in STEM is a huge hot-button topic. I guess I am just a bit annoyed that I posted a good article on it and that is being ignored, but, boy, howdy, can folks pile on to this inane derail as if your comment on how freaked out these bugs would make you is some huge sexism in STEM hill to die on.
Priorities. (rolls eyes)
The article doesn't say much about their feeding behavior, but if they're anything like other walking sticks, they're herbivores with no defence mechanisms other than camouflage. Think butterflies, but without the wings.
I think the main reason I don't feel particularly creeped out by them, though, is that they have the sort of cartoonish physiology that I'd expect of a mostly-harmless Mario-game enemy.
Is there any other kind of drop bear?
Why is that better?
Have you never heard a little girl scream? It's not the same as the sound of a little boy.
Let's not let political correctness wash away every difference that makes individuals special.
I disagree, all little humans learn how to make that piercing scream often attributed to little girls. Little boys will likely do it less as they begin to be socialized and thus wedged into gender roles, but they definitely do "scream like little girls".
You apparently don't actually know any little boys and girls because their screams sound nothing alike. Boys do manage a nice scream, but it doesn't sound the same, especially past the age of 3.
> Little boys will likely do it less as they begin to be socialized and thus wedged into gender roles
Again with this nonsense canard? Why is there such an inability to recognize that boys and girls are different? Next you'll tell me people aren't born knowing what gender they are, but rather it's "socialized" into them.
A desire for equality will not be achieved by erasing all differences, but by celebrating all differences, and recognizing each is valuable in its own way.
I worked as a neurology technician for four years, doing tests on a patient load that was half paediatric, plenty of whom had an induced drowsy state to bring out epileptic activity. Drowsy kid, strange environment, strange person touching their head, and sometimes autistic. For four years, I spent half the day in the presence of children's screams. I promise you that they don't sound different, and certainly not to the qualitative level you're trying to shoehorn in here.
And seriously, it's not like the statement was a neutral explanation. It's a trope - no-one says "run away screaming like a little boy". Trying to defend it as a serious qualitative explanation of the actual sound made is nonsense.
> A desire for equality will not be achieved by erasing all differences, but by celebrating all differences, and recognizing each is valuable in its own way.
I wholeheartedly agree - we need to recognise people as individuals and individual differences. Hence why we need to drop generalising tropes like "run away screaming like a little girl", because they are about stereotypes, not individuality. There are plenty of girls out there who don't do that - my mother's earliest memory is of patting a hairy spider, for example. No 'running away screaming' for that individual.
How on earth you defend "like a [demographic]" as some sort of comment in support of recognising individuality is beyond me.
I can't find anything on children screaming.
Screaming isn't particularly well-articulated :)
That just depends on what you mean by gender. There are many things around gender that are social constructs. For example, pink being a "feminine" colour. Do you believe that DNA encodes females to prefer pink?
Of course, the article you reference doesn't claim that there was a reversal as many others do, but that the colors were simply not as gendered in the past, which seems almost certainly true.
And in the vein of special individuals, there are little girls who love and hate insects, and little boys who love and hate insects. Perhaps a more original phrase or analogy would be better: I would scream like a Dryococelus australis being attacked by rats.
Apparently you have not met any. They don't sound anything alike, except maybe as newborns.
> there are little girls who love and hate insects
He just said scream like a little girl, there was no connotation of girls hating or loving insects. Just a sound.
I don't know about that.
My 3.5yo daughter has a 4.5yo male best friend. When they're running about squealing, it's pretty hard to tell their squeals apart.
There was, however, the connotation that girls are prissy and easily scared.
Also, the trope is "run away, screaming like a little girl", not just "screaming like a little girl".
So what is the problem then? If they sound the same, then what difference does it make if he said "scream like a little girl" or "scream like a little boy" or "scream as a child"?
So then you take a step back and stop being so literal (which is also nonsensical because the scream of either young child would suffice in the example) and say "Why is the expression always 'scream like a little girl' vs 'scream like a little boy?" Why would a grown male say 'little girl" and change sexes in their example? It's because we have a stereotype of girls being more fearful and generally inadequate when faced with such things than boys. A small girl screaming is cute and funny because it reinforces stereotypes around them needing protection and not being self sufficient. A small boy screaming is not cute and funny as boy's are expected to be brave and not scared - it's a sign of weakness if they do. It's an inaccurate stereotype and slightly demeans girls and/or sends messages on our how they're supposed to act. "Screamed like a little girl. Throws a ball like a girl" It's death by a thousand little subtle lashes.
So "would scream like a scared little child" conveys perfectly what you might want to get across without demeaning one sex over the other. If you want to be sex specific then use your own vs feeling the need to switch to the other side.
And I would scream like a little girl if I had to be faced with these tree lobsters -- just like I do when faced with flying, giant roaches in godforsaken swampy Georgia.
Give me a big assed spider or snake any day.
You can keep all your conjecture about what wusses little girls are supposed to be. I'm no wuss. Scream like a little girl conveys an evocative image of someone being shrill. The big difference between little girls and little boys is that little girls have the world's permission to express their feelings. Little boys are supposed to "not cry" and shit like that.
Also, while we are having this conversation: The correct interpretation of "Fights like a girl" is "So, they fight dirty?" Have you ever seen a cat fight in junior high? Gebus. Claws in your face and hair being torn out.
FYI: Statistically speaking, if you get into a knife fight with a man, you are highly likely to come away with minor defensive wounds on your arms because men are aggressive and will attack overhanded. Women don't want to cut you. They hold it low down, in a defensive position, and only cut you if you push them into the position of a cornered rat. The result: They gut you or stick it up under your ribs into a vital organ, like your heart. You are much more likely to die from being knifed by a woman than a man.
So maybe you should educate yourself a bit more about what really goes on in this world before you lecture people about promoting gender stereotypes. Because your bias is showing and it isn't pretty at all.
Yes. Because they are girls. I don't know what deluded world, or ultra PC world, you live in where boys and girls are the same, or act the same.
The existence of girls that don't scream, and boys that do, despite no difference in nurture is the evidence that it's entirely nature.
It's not absolute "all girls scream", it's simply that more girls than boys do so - much more. And there is nothing whatsoever wrong with that, or with noticing that.
Embrace the differences!
But you really don't care about science. Because you are marxist ideologue and not scientist.
Just next time when firemen rescue people trapped in house demand that in 50% cases they rescue men first. Fight this female hurting culture it is 2015 for goodness sake!!! Not that human genome haven't changed in any significant way in the past 10,000 years
It says that they've established a captive population of giant stick insects on Lord Howe, and they were planning to start eradicating rodents this year:
"The plan is to eradicate the rats and mice from conservation areas on Lord Howe Island in 2015, and then reintroduce the captive-bred stick insects, and their natural predators – a sub-species of boobook owl. This AU$9 million project has just been approved last month, as announced by Federal Environment Minister Tony Burke and NSW Environment Minister Robyn Parker. According to the government press release, they hope to wipe out more than 130,000 rodents using poison baits, some dropped by air, in allocated conservation areas. Special ‘arks’ will be used to protect native, endangered species until the rodents are gone."
If we could wipe rats and restore the unique ecosystem some other species could re-flourish again.
Like this fligthless bird, the Lord Howe Island Woodhen, only 15 of those birds remained in 1980 in the world, about 300 birds currently:
Or this beautiful endemic stag bettle
this exclusive snail:
some birds will benefit also
and also this big bush cockroach:
And also other 950 endemic species
on the one hand, this is evolution in action, the habitat for this animal was decreased by the presence of a successful predator.
on the other, rats have no sympathy from me, and we have plenty of them around, so why not wipe them out to allow insects to flourish?
somehow killing a bunch of rats to allow a failed species to reclaim its territory seems wrong. so i lean towards letting this insect take its chances in its tiny little habitat.
if we were talking about exterminating people to make room for any of the species we have destroyed it would be a no-brainer...
Competition only "works" when everyone is playing by the same rules. This means that we throw off the equilibrium for the rest of the planet because we play by different rules. In fact, our intelligence is such that I don't even think we're playing the same game any more.
keeping that island rat free is going to be a constant battle, because rats are so good at spreading by using our transportation as a vector.
like i say, i'm in two minds... i do think its incredibly sad to wipe out a species by introducing another like this. we lose something really special and unique. i just can't give equal weight to the argument because its so flooby dooby and driven by emotion rather than sensiblity.
also, i don't think we play by different rules... we classically out compete every other species in almost every habitat. we are the pinnacle of evolution today. the fallout of our actions are nature in action, despite the temptation to treat humans with some special place of privilege in the natural order of things... that being said, our alturism is part of that success, and is ultimately the source for the feeling argument.
Now seeing that we're already altering our environment however we want, why not alter it back? Especially if you consider humans to be playing by the same rules. In that light, who cares about the rats? We out competed them, we'll alter things in ways that please us.
but yes, you are right about altering it back. this is why our altruism and the 'feeling' argument has more merit than logically it should. (for me)
We are the only ones that significantly alter our environment. If there was a continuum of intelligence, with a fairly smooth and not-to-concave curve, I would be inclined to agree with you. But there isn't, it's a bunch of animals that have no appreciable ability to alter their environments purposefully, and then us. Therefore anything we do falls in the "contaminated experiment" category.
i'm yet to see evidence of free will, i'm not convinced i am not just a machine doing its thing like everything else is... also, this feels like a religious argument from both sides.
See the attempt to remove hedgehogs from some Scottish islands - very expensive failure.
April 2003 - Attempts to begin a cull of hedgehogs on North Uist in the Western Isles have got under way.
April 2005 - Animal rights activists are trying to rescue hedgehogs as an annual cull gets under way in the Outer Hebrides.
October 2005 - Protest over annual hedgehog cull
April 2007 - The board of Scottish Natural Heritage (SNH) has decided to suspend its cull of hedgehogs in the Western Isles.
February 2010 - Hebridean hedgehogs: a prickly issue The Uists cull has already cost more than £1m, but we should question the causal link between bird and hedgehog populations
February 2011 - £1.3m hedgehog cull to save islands' birds eggs 'fails'
Or, to think of it another way: It's only clickbait if the headline is more interesting then the actual article. For this article, that's not the case at all.