if we wanted to study ways to increase growth of teenagers by emulating effects of whatever chemicals that make tall people tall, could we use low cost mammals like pigs or dogs for the experimentation? Or are body length determining mechanisms very different between species, such as between us and dogs?
I don’t think the relevant mechanisms are understood all that well, but they are probably to do with chemical gradients within the developing embryo. I think most people who study these sorts of things would be pretty surprised if the mechanisms turned out to be radically different in humans and other mammals.
Why, though, should we want taller teenagers? Most of them are too damn tall already!
could you clarify the embryo bit? Looking at it naively, all babies are born similar in size, then by age of 8 there is some height difference and during teenage years there is the major growth spurt, with some growing much more than others - so I guess I don’t see where the embryo as such comes in here.
Full-term babies are between 18 and 22 inches long at birth… that’s a pretty big difference already. And babies and toddlers can grow at very different rates, too. I know two young brothers who are 22 months apart and they are an inch different in height and about 5 lbs in weight, this has been true since the younger was 8 or 9 months old. The older brother is not a small kid, he’s about 50% on the charts, but the younger is a beast like their father (all muscle - poor kid can’t swim cause he sinks like a rock).