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It's not stupidity that leads birds to raise cuckoos eggs it's the fact that cuckoos are mobsters who check up after laying and if their egg/chick isn't still t

It's not stupidity that leads birds to raise cuckoos eggs it's the fact that cuckoos are mobsters who check up after laying and if their egg/chick isn't still there they destroy the entire nest and clutch of eggs. The other species live with the parasitism grudgingly not obliviously!

nullc 4y ago
I thought that at least in some species the brood parasite evicts the other young from the nest-- in this case there would be no reason to not abandon it if it truly were detected.
- hilbert42 4y ago
  The cuckoo actually does this: https://www.youtube.com/watch?v=SO1WccH2_YM https://www.youtube.com/watch?v=SO1WccH2_YM. What I still don't understand is why the paristized birds—here the Reed Warbler—continue to feed the cuckoo chick when it's not in its evolutionary best interest. Surely Reed Warblers know the chick is not their own so what's going on? The only logic I can come up with is that there's a symbiotic relationship between cuckoos and birds that it paristizes that's evolved over millions of years which is that the cuckoo acts as a population control agent. In effect it regulates the population of birds in the area of bushland it covers and thus ensures that there is enough food, territory to nest etc. for all birds in the area. If it's not something like that then the Reed Warbler must be dumb. If neither of those ideas fit then what else could it be? (Look at it this way, the Reed Warbler pair has committed huge resources in building a nest and brooding three eggs. All that is effectively destroyed by the cuckoo so why would a 'sensible' Reed Warbler continue to feed the cuckoo chick?)
  - vagrantJin 4y ago
    > why would a 'sensible' Reed Warbler continue to feed the cuckoo chick Same reason humans raise step kids. Assumed Parental obligations.
    - hilbert42 4y ago
      Probably so, but perhaps we should research it more to know for certain. If this is inate behavior across the much of the animal kingdom then it becomes a fact with useful potential.
      - vagrantJin 4y ago
        Eh. I can't see the potential usefulness of that information at least not enough to warrant research. By and by I suppose.
        hilbert42 4y ago
        Since posting that and other earlier comments I've read up on this matter and particularly on brood parasites both on Wiki and elsewhere and I'm much better informed now (see these debates are actually useful). :-) The short and overly simplified explanation is that a considerable amount of research has been done over many years and it's deemed useful for various reasons, understanding species longevity, rates of extinction, the evolutionary one-upmanship between the parasites and those who stand to lose by being parasitized and so on. What is clear is that there are many quite logical and reasonable theories about said matters but little actual proof so more research is needed before any definitive conclusions are drawn. At least on the matter of brood parasites this wiki is a good place to start as it provides a reasonably comprehensive overview (other sites are more specific and some I've only skimmed so I'm not in the position to comment about them): https://en.m.wikipedia.org/wiki/Brood_parasite https://en.m.wikipedia.org/wiki/Brood_parasite. One thing for certain is that these matters are complex and often there are multiple-threaded explanations (that is different explanations can simultaneously apply to each case without conflict).
prennert 4y ago
Maybe cuckoos do this to breed birds for their acceptance of cuckoos eggs, which might help birds learning to accept them.
hilbert42 4y ago
OK, that makes sense whilst the clutch of eggs remain in the nest but once the cuckoo chick has ejected them there is no reason for the birds to continue nesting there. As I said to nullc there has to be some other reason why, say, the Reed Warbler continues to feed a cuckoo chick twice its size with now no viable offspring of its own if it's not oblivious to the fact (see video in that post).

nullc 4y ago

I thought that at least in some species the brood parasite evicts the other young from the nest-- in this case there would be no reason to not abandon it if it truly were detected.

hilbert42 4y ago
The cuckoo actually does this: https://www.youtube.com/watch?v=SO1WccH2_YM https://www.youtube.com/watch?v=SO1WccH2_YM. What I still don't understand is why the paristized birds—here the Reed Warbler—continue to feed the cuckoo chick when it's not in its evolutionary best interest. Surely Reed Warblers know the chick is not their own so what's going on? The only logic I can come up with is that there's a symbiotic relationship between cuckoos and birds that it paristizes that's evolved over millions of years which is that the cuckoo acts as a population control agent. In effect it regulates the population of birds in the area of bushland it covers and thus ensures that there is enough food, territory to nest etc. for all birds in the area. If it's not something like that then the Reed Warbler must be dumb. If neither of those ideas fit then what else could it be? (Look at it this way, the Reed Warbler pair has committed huge resources in building a nest and brooding three eggs. All that is effectively destroyed by the cuckoo so why would a 'sensible' Reed Warbler continue to feed the cuckoo chick?)
- vagrantJin 4y ago
  > why would a 'sensible' Reed Warbler continue to feed the cuckoo chick Same reason humans raise step kids. Assumed Parental obligations.
  - hilbert42 4y ago
    Probably so, but perhaps we should research it more to know for certain. If this is inate behavior across the much of the animal kingdom then it becomes a fact with useful potential.
    - vagrantJin 4y ago
      Eh. I can't see the potential usefulness of that information at least not enough to warrant research. By and by I suppose.
      - hilbert42 4y ago
        Since posting that and other earlier comments I've read up on this matter and particularly on brood parasites both on Wiki and elsewhere and I'm much better informed now (see these debates are actually useful). :-) The short and overly simplified explanation is that a considerable amount of research has been done over many years and it's deemed useful for various reasons, understanding species longevity, rates of extinction, the evolutionary one-upmanship between the parasites and those who stand to lose by being parasitized and so on. What is clear is that there are many quite logical and reasonable theories about said matters but little actual proof so more research is needed before any definitive conclusions are drawn. At least on the matter of brood parasites this wiki is a good place to start as it provides a reasonably comprehensive overview (other sites are more specific and some I've only skimmed so I'm not in the position to comment about them): https://en.m.wikipedia.org/wiki/Brood_parasite https://en.m.wikipedia.org/wiki/Brood_parasite. One thing for certain is that these matters are complex and often there are multiple-threaded explanations (that is different explanations can simultaneously apply to each case without conflict).

prennert 4y ago

Maybe cuckoos do this to breed birds for their acceptance of cuckoos eggs, which might help birds learning to accept them.

hilbert42 4y ago

OK, that makes sense whilst the clutch of eggs remain in the nest but once the cuckoo chick has ejected them there is no reason for the birds to continue nesting there. As I said to nullc there has to be some other reason why, say, the Reed Warbler continues to feed a cuckoo chick twice its size with now no viable offspring of its own if it's not oblivious to the fact (see video in that post).