Lessons learnt in mother's womb - Parenting in animal world - Part II

I came across an interesting article in the news paper recently titled "Birds groom chicks prenatally". This was a research conducted at the University of Cambridge on Canary birds. As per the research, the mother bird communicates with their developing chicks before even they hatch by leaving messages in the egg. The message would be, the kind of life that they will face after birth. Accordingly the chicks adjust the development with regard to their feeding pattern.

The chicks who are reared by generous parents beg more vociferously for food after hatching but those chicks who are raised by meaner parents will end up begging far less as they know that it will not yield any response from their parents. Based on the messages in the egg, the nestlings gain weight more rapidly so as to match the demands to the parent's supply of food. This way they can avoid either begging too little or wasting effort on unrewarding begging. Phew! That is one big lesson that the chicks have to learn.

I guess these are genetically ingrained into each species from time immemorial based on the principle of survival instincts. Coming to human babies, many a time I have seen cases where babies born to mothers who are above normal weight are generally thin or are of average weight. Whereas sometimes I have seen babies born to mothers who are thin or almost underweight to be quite chubby. Although here it might not be in the context of generous or mean parenting but economic consideration and health aspect of the mothers which might play a very crucial role. What's your view?