4 ms·

Why do animals adopt?

47 points by dnetesn 2y ago

sinuhe69 2y ago
Or maybe the author has read too much into it! Maybe it's just a drift of the instinct animals have for their offspring, an association error of the animal's brain. Not unlike the mistake they make when they eat (and sadly die) from plastic litters.
- actionfromafar 2y ago
  The question "why" has several "layers", if you will. A drift off instinct can be more than "just" something. Many of our own behaviours must have some roots in such drifts, yet are more commonly discussed in terms of culture etc.
- Timwi 2y ago
  Would this imply that humans’ propensity to keep pets is also an association error in the brain?
  - ElevenLathe 2y ago
    I think a tendency toward animal husbandry, either genetic or cultural, is just clearly an evolutionary benefit. We domesticated all the various things we keep as pets and livestock for what were good reasons in the ancestral environment, even if those reasons don't persist for most people today.
Scandiravian 2y ago
If a sufficiently large part of a population behaves altruistically, it does makes sense for adoption to happen. In the example with the elephant seals, if a mother becomes separated from her calf during a storm, having a predisposition in the population to adopting someone else's calf is beneficial to the mother, as her offspring might be adopted as well
- MrMcCall 2y ago
  Yes. As well, prey animals also have better safety with greater numbers.
- jstanley 2y ago
  That's not how natural selection works.
  - ujikoluk 2y ago
    It is though, at the group level. The groups that adopt will have better survival than groups that don't, if the environment is such that parents regularly die while the cubs are small.
    - shellfishgene 2y ago
      If group selection happens is still much debated among biologists, and not at all resolved!
      - beeflet 2y ago
        Do you think group selection applies to eusocial species such as bees? It must. If so, imagine a species that is incrementally less social than eusocial. Unless there is some threshold degree of sociality required for group selection, then there clearly some level of group selection occurs for other animals (whether or not it's a major effect)
        shellfishgene 2y ago
        This is usually explained by kin selection, which is different from group selection. I'm not an expert on either though.
  - Toine 2y ago
    Please explain since you seem to have a PhD in darwinism.
rwmj 2y ago
Complicated explanations for what is probably quite simple: The genes are sequences of DNA which have only very indirect and complicated, non-linear effects on the outcome. In this case the genes code for "I must care for my offspring". On very rare occasions this doesn't quite work advantageously (in a strict evolutionary sense), but mostly it does. There may be no practical set of mutations that could fine-tune this behaviour (such as: dozens of changes would be required, but the outcome is negative unless all happen together), so it continues this way.
- gpderetta 2y ago
  I agree that the local optimum one is a good explanation.
- zmgsabst 2y ago
  Assessing benefit is complicated: A genetic lineage may both lose resources to adopting and gain them from being adopted at different times — and where that nets out over 1000+ generations isn’t immediately clear. Survival benefits from having more members at the cost of some resources now is even less clear. This may be a case of a benefit being selected for on a multi-generational scale; or it could be as you say and a disadvantage.
  - FrustratedMonky 2y ago
    Nobody is actually doing the calculations, the decisions are arrived at from what evolution has built into us, hard wired based on what has worked in order to get us here. "Already I can see the chain reaction: the chemical precursors that signal the onset of an emotion, designed specifically to overwhelm logic and reason. An emotion that is already blinding you to the simple and obvious truth"
  - rwmj 2y ago
    My argument isn't about if it's advantageous or not. It's that the mechanism (DNA, a long string) may not be well-suited to expressing and adjusting very complex emergent behaviours in the phenotype. There may either not be a way at all to express "show strong maternal instincts but reject all non-related children and surrogate children like pets", or there are too many steps to get there and natural selection would never find it in any reasonable evolutionary timescale.
mseepgood 2y ago
Probably for the same reasons humans adopt, since we are animals, too. Just ask people who adopted for their reasons.
shellfishgene 2y ago
Not sure what the point of the article is. Caring for young is a strong behavioural program, and errors happen, seems to be the summary, not too enlightening. They could have mentioned cuckoos, which actively exploit these errors.
moomin 2y ago
I think people sometimes treat natural selection as making cold cost/benefit kin-selection decisions on a case by case basis and mind controlling the creatures to make those choices. I am straw manning, but my point is it doesn't work that way. It develops predispositions and behaviours. How those predispositions and behaviours play out is the choice of the individual creature (including the case when the creature is human).
- FrustratedMonky 2y ago
  "develops predispositions and behaviors" Can't you take 'predisposition' to be a little more hardline, and that it removes all 'choice'. We are so 'predisposed' by biology/chemistry that animals, and humans, don't have any agency of choice, no free will to calculate anything.
  - ithkuil 2y ago
    Removing all choices removes the flexibility. It appears that occasionally straying from the hard rules provides an overall better fitness to the organism given that the fitness landscape (or fitness seascape) changes with time
  - kdmccormick 2y ago
    This is two ways of saying the same thing. To use a computing metaphor, every animal has "buildtime" predispositions and "runtime" choice-making ability. That "runtime" decision making is based on exercising free will, but of course free will is a biologically built-in capability which executes on the deterministic "VM" that is our physical universe. i.e., we have free will from the perspective of ourselves, but if you zoom out, that free will is just another predetermined physical phenomena.
    - FrustratedMonky 2y ago
      I think the issue is 'could any other decision be made'. In the computer analogy, if the 'run time' always arrives at the same answer, because that is the answer from the calculation. Then was there ever a choice? I guess this and the other comments are really saying just because we have the illusion of free will from our perspective, just assume a choice is being made and roll with it. Don't get tied in knots about the question of free-will, we know we don't have it, but just assume we do in order to make our perspective work out.
byyoung3 2y ago
probably the same reason dogs hump pillows
stavros 2y ago
Because evolution made sex feel good, and caring for kids feel good, and the two together lead to positive evolutional outcomes. It never specifically made "caring for your kids" good.
Gravityloss 2y ago
Bird species have different looks and mating rituals that usually prevent mixups but sometimes it happens: https://en.wikipedia.org/wiki/Rackelhahn https://en.wikipedia.org/wiki/Rackelhahn One theory is it requires multiple phases. First an unintenional egg mixup. First there are eggs laid by one bird, then it's abandoned for some reason and another bird of a different species lays eggs on top. All the chicks are raised by the parents as if of the species of the latter bird, but one or more of the hatchlings are actually from the first batch, a different species. The chicks will absorb enough of the habits as to mate with their "social species" instead of their "biological species". (Am not a biologist and don't know the precise terms).
tail_exchange 2y ago
As the article says, animals are not automatons, despite our tendency to see them as so. Maybe they do it for similar reasons why we adopt pets? Biologically, it doesn't make sense to keep a modified wolf in my house competing for my resources either.
- rqtwteye 2y ago
  Exactly. Us humans do a lot of things that aren’t optimal but make us feel good for some reason. Why do people like cats? They often are assholes but we still love them. Why would animals be different?
- sorokod 2y ago
  You can feed and care for an extra mouth and still procreate. Animals tend not to have such luxury, some will abandon the weak offspring because of that.
jonnycomputer 2y ago
There is a tendency to call something an evolutionary puzzle if some behavior is not optimal, and so elaborate, and often quite clever, possible explanations for why it's secretly optimal are devised. But it's a mistake to think that non-optimal phenotypes require special explanations, when the obvious one is at hand: the optimal solution hasn't been found yet. In this case, the mechanisms that ensure that young are cared for are simply being triggered or activated by situations it wasn't "designed for", and nothing has evolved to prevent that from happening because it's an infrequent occurrence in the first place (and perhaps because any solution to it would be more expensive that it's worth?). Life works with what its got, and natural selection (and other forms of selection) are not explanations, they're frameworks, models of a type of process. Actual explanations involve actual causal chains with actual stuff in the world.
- adamc 2y ago
  Yep. Evolution is really just a description of the consequences of differential reproduction. Rare behaviors (adoption) that are not optimal but which are driven by drives (better motherhood) that may have big evolutionary upsides may simply not be selected against very effectively, and evolution is always limited by the pool of mutations and what is possible for the organism at that point. If there is no mutation that both eliminates adoption and preserves the beneficial effects of the drive, it may not happen...
  - jonnycomputer 2y ago
    Yeah, the mutation or recombination path that would lead to a solution may just be too far away, and involve troughs in the fitness landscape.
- antithesizer 2y ago
  This is not necessarily suboptimal behavior; given that any genetically determined behavior will constitute a categorical imperative among those individuals carrying the genes, and whose offspring gets orphaned is to some extent random, the benefit of having their own offspring cared for in the event of their untimely death may outweigh the cost of raising offspring with whom they have less genetic material in common.
jonnycomputer 2y ago
Yeah, and why don't my fingers shoot laser beams? Seems useful, but I don't have them. Evolutionary puzzle???????????
rm445 2y ago
I'm curious whether the whole tree of life being related plays some part in cross-species adoption (and even animal behaviour in general???). In the sense that genes don't 'want' anything, but selection creates a pressure towards overall adaptation and survival... a lion shares a lot of genes with a leopard. Is it pro-genetic-survival in some very broad sense for a lioness to care for a baby leopard? I guess not, if adults of those species compete to the death... but many species don't seem to do a lot of murdering, beyond predation for food. Animals sometimes seem quite incurious about other activity close to them, except when they need to eat. Could there be some small selection pressure towards live-and-let-other-DNA-live?
VoodooJuJu 2y ago
Could it be that animals, like humans, aren't just sacks of chemicals? Could it be they're not computer programs, but that they are, in fact, animals? This is why I despise practically every discussion of "why" when it comes to talking about observed traits and evolution like this. People invent this bizarre deterministic model of life as it it were purely chemical or computational and could be controlled & understood as such. As if every single little trait has design intent. You have one guy in this thread that's like, "Would this imply that humans’ propensity to keep pets is also an association error in the brain?". Like holy shit dude, I don't know, but maybe people just like pets. Maybe pets like pets. Maybe pets like us. Maybe we aren't computer programs whose nature is defined by scripts and wiring. "Association error". The fuck? We're not computer programs. We don't have "errors". Like what a dull and inhuman lens to view the world with: "We're all just computers", or "We're all just a bunch of chemicals". I wonder, do you also think of me as a computer or a chemical sack? Do you view my child that way? My cat? If you do, that disturbs me, because then you may be tempted to treat us as such, when we're all so much more than that.
- shrx 2y ago
  > Could it be that animals, like humans, aren't just sacks of chemicals? So far, nobody has proven otherwise.
ljf 2y ago
I've often pondered why some animals make friends. I grew up on a small farm, where we mainly kept sheep. Most of the year the ram would have next to no interest in the yews (female sheep), unless there was some sort of threat - he'd just be off doing his own thing. Once my mum bought a calf as auction as it was so cheap (from memory 20p - most cows are sold in lots of 6, but this was an odd lot and no-one bid) - the calf loved us and wanted to be with us whenever we were in the field (and to be bottle fed), but the rest of the time would hang out with the ram. That September a family brought a pet duck to us as their daughter couldn't take it to university and the parents didn't want to look after it. We said sure, and as soon as they left we put it in the pond. The geese we had started to attack it, and the duck ran out of the pond and hid between the legs of the cow who just happened to be near. And that was it - for the rest of the year the duck, cow and ram were always together - they'd pace up and down the field together and at night the duck would either sleep between the cows legs, or curled up to it, if the cow was seated/lying down. They genuinely seemed to all get a lot from the bond they shared as three 'others'. Sadly a couple of years later, after a few of our chickens were eaten by a fox, my mum tried to put the duck away each night. As she was trying to catch it the cow started stamping to tell her to leave the duck alone, and accidentally stamped on the duck, breaking its leg. We took it to a city farm and 'gifted' it to them - but I am told it made friends with their ducks, though I didn't recognise it when we visited - but I was only about 8 at the time.
tristramb 2y ago
If you want to explain a particular type of animal behaviour you should probably familiarize yourself with Tinbergen's Four Questions: https://www.youtube.com/watch?v=8NRU6iH5lzs https://www.youtube.com/watch?v=8NRU6iH5lzs
sorokod 2y ago
It is just a bug in the system, the parental instinct misfires. Similar to the cases where parentd abandon their offspring for, what to us look like, superficial reasons. Cookoos exploit the system via this bug.

47 points by dnetesn 2y ago

Or maybe the author has read too much into it! Maybe it's just a drift of the instinct animals have for their offspring, an association error of the animal's brain. Not unlike the mistake they make when they eat (and sadly die) from plastic litters.

actionfromafar 2y ago
The question "why" has several "layers", if you will. A drift off instinct can be more than "just" something. Many of our own behaviours must have some roots in such drifts, yet are more commonly discussed in terms of culture etc.
Timwi 2y ago
Would this imply that humans’ propensity to keep pets is also an association error in the brain?
- ElevenLathe 2y ago
  I think a tendency toward animal husbandry, either genetic or cultural, is just clearly an evolutionary benefit. We domesticated all the various things we keep as pets and livestock for what were good reasons in the ancestral environment, even if those reasons don't persist for most people today.

Scandiravian 2y ago

If a sufficiently large part of a population behaves altruistically, it does makes sense for adoption to happen. In the example with the elephant seals, if a mother becomes separated from her calf during a storm, having a predisposition in the population to adopting someone else's calf is beneficial to the mother, as her offspring might be adopted as well

MrMcCall 2y ago
Yes. As well, prey animals also have better safety with greater numbers.
jstanley 2y ago
That's not how natural selection works.
- ujikoluk 2y ago
  It is though, at the group level. The groups that adopt will have better survival than groups that don't, if the environment is such that parents regularly die while the cubs are small.
  - shellfishgene 2y ago
    If group selection happens is still much debated among biologists, and not at all resolved!
    - beeflet 2y ago
      Do you think group selection applies to eusocial species such as bees? It must. If so, imagine a species that is incrementally less social than eusocial. Unless there is some threshold degree of sociality required for group selection, then there clearly some level of group selection occurs for other animals (whether or not it's a major effect)
      - shellfishgene 2y ago
        This is usually explained by kin selection, which is different from group selection. I'm not an expert on either though.
- Toine 2y ago
  Please explain since you seem to have a PhD in darwinism.

rwmj 2y ago

Complicated explanations for what is probably quite simple: The genes are sequences of DNA which have only very indirect and complicated, non-linear effects on the outcome. In this case the genes code for "I must care for my offspring". On very rare occasions this doesn't quite work advantageously (in a strict evolutionary sense), but mostly it does. There may be no practical set of mutations that could fine-tune this behaviour (such as: dozens of changes would be required, but the outcome is negative unless all happen together), so it continues this way.

gpderetta 2y ago
I agree that the local optimum one is a good explanation.
zmgsabst 2y ago
Assessing benefit is complicated: A genetic lineage may both lose resources to adopting and gain them from being adopted at different times — and where that nets out over 1000+ generations isn’t immediately clear. Survival benefits from having more members at the cost of some resources now is even less clear. This may be a case of a benefit being selected for on a multi-generational scale; or it could be as you say and a disadvantage.
- FrustratedMonky 2y ago
  Nobody is actually doing the calculations, the decisions are arrived at from what evolution has built into us, hard wired based on what has worked in order to get us here. "Already I can see the chain reaction: the chemical precursors that signal the onset of an emotion, designed specifically to overwhelm logic and reason. An emotion that is already blinding you to the simple and obvious truth"
- rwmj 2y ago
  My argument isn't about if it's advantageous or not. It's that the mechanism (DNA, a long string) may not be well-suited to expressing and adjusting very complex emergent behaviours in the phenotype. There may either not be a way at all to express "show strong maternal instincts but reject all non-related children and surrogate children like pets", or there are too many steps to get there and natural selection would never find it in any reasonable evolutionary timescale.

mseepgood 2y ago

Probably for the same reasons humans adopt, since we are animals, too. Just ask people who adopted for their reasons.

shellfishgene 2y ago

Not sure what the point of the article is. Caring for young is a strong behavioural program, and errors happen, seems to be the summary, not too enlightening. They could have mentioned cuckoos, which actively exploit these errors.

moomin 2y ago

I think people sometimes treat natural selection as making cold cost/benefit kin-selection decisions on a case by case basis and mind controlling the creatures to make those choices. I am straw manning, but my point is it doesn't work that way. It develops predispositions and behaviours. How those predispositions and behaviours play out is the choice of the individual creature (including the case when the creature is human).

FrustratedMonky 2y ago
"develops predispositions and behaviors" Can't you take 'predisposition' to be a little more hardline, and that it removes all 'choice'. We are so 'predisposed' by biology/chemistry that animals, and humans, don't have any agency of choice, no free will to calculate anything.
- ithkuil 2y ago
  Removing all choices removes the flexibility. It appears that occasionally straying from the hard rules provides an overall better fitness to the organism given that the fitness landscape (or fitness seascape) changes with time
- kdmccormick 2y ago
  This is two ways of saying the same thing. To use a computing metaphor, every animal has "buildtime" predispositions and "runtime" choice-making ability. That "runtime" decision making is based on exercising free will, but of course free will is a biologically built-in capability which executes on the deterministic "VM" that is our physical universe. i.e., we have free will from the perspective of ourselves, but if you zoom out, that free will is just another predetermined physical phenomena.
  - FrustratedMonky 2y ago
    I think the issue is 'could any other decision be made'. In the computer analogy, if the 'run time' always arrives at the same answer, because that is the answer from the calculation. Then was there ever a choice? I guess this and the other comments are really saying just because we have the illusion of free will from our perspective, just assume a choice is being made and roll with it. Don't get tied in knots about the question of free-will, we know we don't have it, but just assume we do in order to make our perspective work out.

byyoung3 2y ago

probably the same reason dogs hump pillows

stavros 2y ago

Because evolution made sex feel good, and caring for kids feel good, and the two together lead to positive evolutional outcomes. It never specifically made "caring for your kids" good.

Gravityloss 2y ago

Bird species have different looks and mating rituals that usually prevent mixups but sometimes it happens: https://en.wikipedia.org/wiki/Rackelhahn https://en.wikipedia.org/wiki/Rackelhahn One theory is it requires multiple phases. First an unintenional egg mixup. First there are eggs laid by one bird, then it's abandoned for some reason and another bird of a different species lays eggs on top. All the chicks are raised by the parents as if of the species of the latter bird, but one or more of the hatchlings are actually from the first batch, a different species. The chicks will absorb enough of the habits as to mate with their "social species" instead of their "biological species". (Am not a biologist and don't know the precise terms).

tail_exchange 2y ago

As the article says, animals are not automatons, despite our tendency to see them as so. Maybe they do it for similar reasons why we adopt pets? Biologically, it doesn't make sense to keep a modified wolf in my house competing for my resources either.

rqtwteye 2y ago
Exactly. Us humans do a lot of things that aren’t optimal but make us feel good for some reason. Why do people like cats? They often are assholes but we still love them. Why would animals be different?
sorokod 2y ago
You can feed and care for an extra mouth and still procreate. Animals tend not to have such luxury, some will abandon the weak offspring because of that.

jonnycomputer 2y ago

There is a tendency to call something an evolutionary puzzle if some behavior is not optimal, and so elaborate, and often quite clever, possible explanations for why it's secretly optimal are devised. But it's a mistake to think that non-optimal phenotypes require special explanations, when the obvious one is at hand: the optimal solution hasn't been found yet. In this case, the mechanisms that ensure that young are cared for are simply being triggered or activated by situations it wasn't "designed for", and nothing has evolved to prevent that from happening because it's an infrequent occurrence in the first place (and perhaps because any solution to it would be more expensive that it's worth?). Life works with what its got, and natural selection (and other forms of selection) are not explanations, they're frameworks, models of a type of process. Actual explanations involve actual causal chains with actual stuff in the world.

adamc 2y ago
Yep. Evolution is really just a description of the consequences of differential reproduction. Rare behaviors (adoption) that are not optimal but which are driven by drives (better motherhood) that may have big evolutionary upsides may simply not be selected against very effectively, and evolution is always limited by the pool of mutations and what is possible for the organism at that point. If there is no mutation that both eliminates adoption and preserves the beneficial effects of the drive, it may not happen...
- jonnycomputer 2y ago
  Yeah, the mutation or recombination path that would lead to a solution may just be too far away, and involve troughs in the fitness landscape.
antithesizer 2y ago
This is not necessarily suboptimal behavior; given that any genetically determined behavior will constitute a categorical imperative among those individuals carrying the genes, and whose offspring gets orphaned is to some extent random, the benefit of having their own offspring cared for in the event of their untimely death may outweigh the cost of raising offspring with whom they have less genetic material in common.

jonnycomputer 2y ago

Yeah, and why don't my fingers shoot laser beams? Seems useful, but I don't have them. Evolutionary puzzle???????????

rm445 2y ago

I'm curious whether the whole tree of life being related plays some part in cross-species adoption (and even animal behaviour in general???). In the sense that genes don't 'want' anything, but selection creates a pressure towards overall adaptation and survival... a lion shares a lot of genes with a leopard. Is it pro-genetic-survival in some very broad sense for a lioness to care for a baby leopard? I guess not, if adults of those species compete to the death... but many species don't seem to do a lot of murdering, beyond predation for food. Animals sometimes seem quite incurious about other activity close to them, except when they need to eat. Could there be some small selection pressure towards live-and-let-other-DNA-live?

VoodooJuJu 2y ago

Could it be that animals, like humans, aren't just sacks of chemicals? Could it be they're not computer programs, but that they are, in fact, animals? This is why I despise practically every discussion of "why" when it comes to talking about observed traits and evolution like this. People invent this bizarre deterministic model of life as it it were purely chemical or computational and could be controlled & understood as such. As if every single little trait has design intent. You have one guy in this thread that's like, "Would this imply that humans’ propensity to keep pets is also an association error in the brain?". Like holy shit dude, I don't know, but maybe people just like pets. Maybe pets like pets. Maybe pets like us. Maybe we aren't computer programs whose nature is defined by scripts and wiring. "Association error". The fuck? We're not computer programs. We don't have "errors". Like what a dull and inhuman lens to view the world with: "We're all just computers", or "We're all just a bunch of chemicals". I wonder, do you also think of me as a computer or a chemical sack? Do you view my child that way? My cat? If you do, that disturbs me, because then you may be tempted to treat us as such, when we're all so much more than that.

shrx 2y ago
> Could it be that animals, like humans, aren't just sacks of chemicals? So far, nobody has proven otherwise.

ljf 2y ago

I've often pondered why some animals make friends. I grew up on a small farm, where we mainly kept sheep. Most of the year the ram would have next to no interest in the yews (female sheep), unless there was some sort of threat - he'd just be off doing his own thing. Once my mum bought a calf as auction as it was so cheap (from memory 20p - most cows are sold in lots of 6, but this was an odd lot and no-one bid) - the calf loved us and wanted to be with us whenever we were in the field (and to be bottle fed), but the rest of the time would hang out with the ram. That September a family brought a pet duck to us as their daughter couldn't take it to university and the parents didn't want to look after it. We said sure, and as soon as they left we put it in the pond. The geese we had started to attack it, and the duck ran out of the pond and hid between the legs of the cow who just happened to be near. And that was it - for the rest of the year the duck, cow and ram were always together - they'd pace up and down the field together and at night the duck would either sleep between the cows legs, or curled up to it, if the cow was seated/lying down. They genuinely seemed to all get a lot from the bond they shared as three 'others'. Sadly a couple of years later, after a few of our chickens were eaten by a fox, my mum tried to put the duck away each night. As she was trying to catch it the cow started stamping to tell her to leave the duck alone, and accidentally stamped on the duck, breaking its leg. We took it to a city farm and 'gifted' it to them - but I am told it made friends with their ducks, though I didn't recognise it when we visited - but I was only about 8 at the time.

tristramb 2y ago

If you want to explain a particular type of animal behaviour you should probably familiarize yourself with Tinbergen's Four Questions: https://www.youtube.com/watch?v=8NRU6iH5lzs https://www.youtube.com/watch?v=8NRU6iH5lzs

sorokod 2y ago

It is just a bug in the system, the parental instinct misfires. Similar to the cases where parentd abandon their offspring for, what to us look like, superficial reasons. Cookoos exploit the system via this bug.