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August 14

Do Tasmanian Devil babies hold on to a mother's back with their teeth?

I was in a wildlife park in Tasmania a few years ago, and the guide there told me that after Tasmanian Devil babies outgrow the mother's pouch, they ride on her back. He then said that babies often use their teeth to hold on to the back, and that Tasmanian Devil moms have thicker back skins specifically for this reason. I recently tried to look this up online as someone asked me about it, but I cannot find an online source to corroborate this story. Does anyone know if it is true? — Preceding unsigned comment added by 209.112.220.247 (talk) 02:06, 14 August 2020 (UTC)[reply]

The article Tasmanian_devil says that the young do ride on their mother's back, but doesn't say how. RudolfRed (talk) 02:26, 14 August 2020 (UTC)[reply]

This pic seems to show one just using its claws to hang on. HiLo48 (talk) 04:23, 14 August 2020 (UTC)[reply]

Ouch. If that was my young, I'd need a leathery back. --Lambiam 10:10, 14 August 2020 (UTC)[reply]

However, you probably wouldn't grow one "specifically for this reason", which was part of the question. In brief, there's no such thing. See Teleology in biology. --174.89.49.204 (talk) 21:29, 14 August 2020 (UTC)[reply]

"In brief, there's no such thing." That's a bit of an overstatement/over-simplification in itself. You're quite right to link that article for the OP in this context, but the truth of the matter is that, barring substantial research into a given trait, it is hard to know for certain just how adaptive it is with regard to other behaviours. Certainly modern researchers tend to be very suspicious of these Just So Stories and I share your doubts here that the thickness of the hide (even if purely a practical adaption devoid of any influence of spandrels) is adapted for the young so much as to many other factors that make it useful for genetic fitness given the famously aggressive species' ecological niche in general. Since behaviour in this case would not leave physical evidence behind and paleontological evidence would not speak the thickness of the hide and it would be difficult to know if the behaviour itself predates any development of the thickness of the hide itself, the just so story here regarding the babies latching on to the fur would be extremely hard to either prove or disprove, even if researchers had looked into it (which I judge as doubtful in its own right). But it's an exaggeration to say that no such folk evolutionary theory ever bears out. Snow ^{let's rap} 08:01, 15 August 2020 (UTC)[reply]

Getting back to the OP's original question, here are a number of additional images ([1],[2], [3], [4], [5], [6], [7], [8]) which certainly do seem to suggest that the young are in fact getting at least some of their purchase from the jaw and although I wouldn't call any one photo dispositive in this regard, given the fabled jaw strength of the species, I don't see any particularly compelling reason not to believe that they leverage this part of their physiology to to stay adhered to the mother's back. That's far from the sourced answer without speculation that I prefer when answerign questions here, but considering the orignal source from which the OP received this information, I'd say I'm inclined to believe this factoid to be true. Snow ^{let's rap} 08:01, 15 August 2020 (UTC)[reply]

Thanks all for your thoughtful responses. And I fully agree, technically the hypothesis isn't that a thicker back hide is there for this reason, but mothers with a thicker hide would be more likely to successfully grow their babies to maturity. It's just comes more naturally to talk about evolutionary biology in a teleological way. And those pictures are cute!

long term effects of psychiatric drugs on children

Have any long term randomized controlled studies evaluating the effects of childhood exposure to psychiatric drugs (e.g. antidepressants or atypical anti-psychotics) adult outcomes ever been conducted? That is to say, has there ever been a study in which a group of, say 10 year olds were randomly assigned to receive either medication or a placebo and then followed for, say, 15 years to see what effect, if any this treatment had on their eventual outcomes at say the age of 25.

I will note that I am not in any way seeking medical advice rather, I am asking the question after having read a thought provoking book on the subject of these medications. 67.253.78.55 (talk) 18:07, 14 August 2020 (UTC)[reply]

If they didn't need them then that study's fucked up and if they did then giving some a placebo is fucked up. There is maybe a very thin gray area such a study would have to pick patients from for it to not be fucked up. Sagittarian Milky Way (talk) 18:31, 14 August 2020 (UTC)[reply]

Since, for several psychiatric drugs, there is no consensus whether, in the balance, they do more good than harm (just read our article on antidepressants), such a study would not necessarily be unethical. --Lambiam 06:58, 15 August 2020 (UTC)[reply]

There have been many longitudinal studies for various antidepressants and antipsychotics, but I did not readily see any conforming to the specifics of the question. Methodologically, this might be problematic, since the conditions for the medicated group and the control group can hardly be kept constant; that would require not adapting the medication subjects receive to changing needs (and changing insights) in the course of these 15 years. --Lambiam 06:58, 15 August 2020 (UTC)[reply]

This study found a correlation between children being prescribed Ritalin and depression in adolescence – but it was not a controlled study, so no causation can be inferred. --Lambiam 07:14, 15 August 2020 (UTC)[reply]