4 ms·

Chicken and the Egg, for 5-year-olds

• NickRandom 4y ago
  Ah. Yeah, that's a tricky one.... The trouble is that it all boils down to the concept being 'turtles all the way down'when followed to it's logical conclusion. Think of it this way - what created the big bang and what was there first (since things cannot form if there is 'nothing' so it must therefore be 'something' (for whatever any definition of "something"). But then - where did the 'something' come from. Good luck with explaining that to your 5 y.o. and I'm glad that she is curious enough to ponder such things in an analytical way! Btw - If you figure it out, let us know ..... because after over 50 decades of life I still, on idle days, ponder the 'What created the 'something' from the original 'nothing'. In other words – If it is indeed ‘turtles all the way down’ then… what made the original turtle? And what made the 'thing' that made the turtle
• el_sinchi 4y ago
  species A becomes subdivided into 2 variants Ax, Ay those being the same species, can mate (think for instance, citrus variants) but somehow they get separated, and start evolving slowly different, and here's the crux, at some point the genetic changes no longer allow viable reproduction should they mix again, at that point they have evolved into separate species it's not that Humans (Ax) came from ape (Ay) but rather they evolved out from some common ancestor (that may or may not still exists today) when they say "humans descend from apes" does not necessarily mean from actual current modern apes and the flaw in the child's reasoning is that presupposes a linear change "from this point on, we have humans, before, we have apes) that's enough simplification for a 5 year old?
  • trashtester 4y ago
    > it's not that Humans (Ax) came from ape (Ay) but rather they evolved out from some common ancestor (that may or may not still exists today) She knows this already, I did show here pictures of Australopithecus(ape) and Homo Habilis (human). She knows that the mother of the first human was something like an Australopithecus, while the first human was something like Home Habilis. The problem is a logical one. Granted that one Homo Habilis was born from one Australopithecus, who would she mate with to have offspring? Would she commit bestiality with some Australopithecus of her tribe, or did in fact TWO such homo habilis suddenly appear in that tribe in the same generation? (And become Adam and Eve, or something.) The latter would, by common sense, seem to be extremely unlikely. I know the real science behind it. Clearly, the problem is to think about a species as a category that is invariant across time. The real answer is that "The category 'human' is not well defined over evolutionary time, so your question is absurd." That is good answer to a 15-year-old. But I was struggling to come up with a good explanation that would extend my methaphor in a way a 5-year-old might understand.
    • swatcoder 4y ago
      With all due respect. I can’t make sense of this. Apparently, you have to be 15 to imagine gradual transitions between things (slush must be mind blowing for the little one), but 5 year olds are insisting you give thorough answers to questions about rarely-occurring abstract moral concepts like bestiality? I know a few five year olds, and I can’t imagine then asking questions like that or caring how sensible the answer is if they did. I guess their parents just haven’t been teaching them the things you’ve been teaching yours?
      • trashtester 4y ago
        > Apparently, you have to be 15 to imagine gradual transitions between things (slush must be mind blowing for the little one), She is unable to grasp time horizons over millions of years, and tell them apart from intuition that at best goes to 3 digits. Visualizing that the transition between Australopithecus and Homo Habilis as incremental steps over hundreds of thousands of years, I presume, is too hard for her (or for my ability to explain). Maybe she can do it before 15, but not yet, I think. Anyway, fact that we use taxonomies in the first place, is part of the problem. As long as we insist on giving names to ancient life forms, this type of question comes up by itself. > but 5 year olds are insisting you give thorough answers to questions about rarely-occurring abstract moral concepts like bestiality? Not explicitly. She is not aware of the concept. I suppose that's what she was asking. But obviously, it is implicit in the question, don't you think? If we insist in defining an individual as belonging to either Australopithecus or Homo, there must have been a time when someone we label as one mated with someone we label as the other. Obviously, I didn't give her that answer. But I did think it.
• IceMetalPunk 4y ago
  First, let's be clear that the "ape mother" answer implies a distinction between humans and other apes, which is not true. We are all born of ape mothers, because humans are apes. Another issue is that "human" can refer to the Homo sapiens species, or it can also refer to any species in the genus Homo, depending on context and preference. With that out of the way, the biggest problem here is that "species" don't actually exist. There are several different definitions, and they each have arbitrarity and/or striking exceptions. Species are just an intellectual tool humans invented to help us organize our understanding of how different living things are related to each other, but evolution is gradual and messy and doesn't care much for clear separations. So the answer to "who was the father of the first human mother's children" depends on which definition of "species" and which definition of "human" you want to use. If you go with the common idea of "two things are different species if they can't have fertile offspring together" (and ignore all the asexual reproduction and fertile hybrid exceptions), and "human" meaning just Homo sapiens, then... well, you're screwed, really. Because by that definition, the only possible father of the first human's children would have to be one of their siblings, as they definitionally couldn't reproduce with any other existing creatures. I'm not ruling out that such inbreeding happened; however... as I said, to use that definition, you need to ignore fertile hybrids, which is a problem because we know Homo sapiens interbred with other Homo species -- we have the DNA in ourselves to prove it. We are all fertile hybrids in that regard. Meaning the actual father would probably have been a pre-sapiens human species. So perhaps you'd prefer to use the morphological definition instead: "humans are the creatures who look most like modern humans". Obviously, that gets messy and arbitrary, too, because different humans look different, and finding a "different enough" threshold is more preference than anything else. But ignoring that problem, the answer becomes the same: "the father of the first modern-looking human was a species that didn't look modern". Same goes for the genetic definition of species as well; the first human whose DNA was "different enough" for us to call it a modern human had children with someone whose DNA was "different enough" to call it "not a modern human". In the end, the answer is approximately the same: the father of the first modern human would have been a different hominid species.
  • trashtester 4y ago
    > In the end, the answer is approximately the same: the father of the first modern human would have been a different hominid species. The question was not about the father if the first human (regardless of how you define human, as long as you use a sharp definition). I had already told my daughter that the mother (and implicitly father) of the the first human were belonging to the prior species in the chain. (For me "human" was used as Genus Homo, but it doesn't matter if one uses homo sapiens sapiens instead) The difficulty of the question came from my daughter asking who would be the father of the CHILDREN of the first human (assuming the first human was female). Either that male would have to still belong to the previous species, or have been born independently of her as human, somewhat after. Given that the second option is very unlikely. If we set sharp enough criteria for qualifying as human to be able to separate different members of the tribe these individuals lived into either human or non-human, the probability of the first two who qualified would arrive so close in time and independently, is probably near zero. In other words, we must assume that if we insist on splitting indivuals into the categoris of "human" and "not human" at that specific point in time, most likely the father of the children of the first human must have ben non-human. Also, it would be very likely that even the children may have been non-human (or it may be tha the first "human" didn't have any children at all). In fact, it could be a 100 or a 1000 years before another individual was born that qualified according to whatever definition of "human" we pick. And this is when I realized that: > the biggest problem here is that "species" don't actually exist. Not only is any definition of "human" in some way arbitrary, the very act of creating such a definition leads strange contradictions such as above. Intuitively, all members of the tribe that brought us the first humans, would have appeared to us as all being EQUALLY human, had we had some way to observe them directly. To draw some red line between individuals of that group makes no sense. (In fact, being in the same tribe, these individuals would be closely related, and so much more similar to each other than two randomly selected modern humans living today would be.) Also, it doesn't help to just create a new category, since the problems at the boundaries will be precisely the same. In other words, the only thing that makes sense, is to not assign categories of human vs non-human to these individuals at all. The closest thing that would make sense would be to assign some "degree of human-ness". Let's say that the first individual with such human-ness would have a human-ness score of more than 50% would have a score of 50.1%, while the average for the tribe would be 49.7% at the time. By thinking of this transition as a real (as in floating point) number, instead of as a boolean, the problem goes away.
• gus_massa 4y ago
  It's a problem of classification. Imagine you have one of those machines with a red faucet with hot water and a blue faucet with cold water. Then you can classify water as hot or cold and be happy. Until you discover that the temperature of water can be in between. Anyway, if one of your coworkers are going to the machine, you can ask for a glass of cold/hot water and your coworker will understand. It's a useful classification. Something similar happens with Australopithecus vs Homo. The discussion is easier because Australopithecus are dead. The latest Australopithecus were very similar to early Homos. The threshold is arbitrary, like the threshold between hot and cold water. (Apparently transitions of species are very fast, so it's difficult to find fossils of the intermediate steps. I'm not sure if this is confirmed.) So if you take a time machine and go to see the transition, you will find some individuals that are difficult to classify. You will not be able to be sure which one is a Australopithecus and which one is a Homo. Perhaps ir you kill them and cut them in pieces, you can apply some arbitrary threshold like 537.2345 cm^3 of brain, but they will not be happy. Moreover, they will not be able to be sure which one of them is a Australopithecus and which one is a Homo, assuming you can explain the arbitrary threshold to them. I guess it depends on how you build the phylogenetic trees at the individual level. 1) The fist Homo mated with a Australopithecus and some of the children were probably Australopithecus and some Homos. I guess two Homos can mate and have a children that is an Australopithecus. If you mark Homos with a magic invisible painting, they will be mixed with the community and be treated as a normal member of he community and mate with whoever they can. After a while, most will be Homos, but the few remainder Australopithecus will also be just normal members of the community and mate with whoever they can. Note that in some parts Australopithecus lived for a longer time, until the Homos from other areas arrived. In the early year we probably ignored the difference and mated. Later when the difference were bigger we probably killed them or forced them to go away. 2) You go and find the first Homo, and define that all the offspring are Homo and it doesn't matter with who they mate. So the first one must mate with an Australopithecus and repeat that during a few generations until the they have cousins far enough to mate. Note that they will not realize the transition. It's just a different way to use the magic invisible painting, but they will interact exactly like in the other method.