All new mothers who are tired from lack of sleep possibly think that their baby is on a campaign to deny them rest, regardless of how often they feed and change them. According to a biologist this may well be true.
One of the leading evolutionary biologists has presented a theory that the tendency for babies to wake during the night could be related to a Darwinian scheme to make the mother breastfeed more often. This will limit sexual activity, fewer siblings will be born and the child survival changes will increase.
Harvard University professor, David Haig, argues that the effect of breastfeeding is contraceptive and this would have aided our ancestors. The fewer siblings a child had, the lower the competition there was for the scarce resources and the less chance there was of contracting infectious diseases.
Professor David Hag stated that the benefits of delaying another pregnancy could be huge. Shorter time periods between the births of siblings is linked to higher infant mortality rates. The benefits of delaying the birth of another baby may be an instinct used by babies to keep their mothers awake, by having to breastfeed them at all hours of the night.
Professor Haig states that this behaviour is ‘part of our natural heritage’. He added that the father’s genes may be responsible for this action by babies. Evidence gained from babies who suffer a rare developmental condition called Angelman Syndrome (AS), which is known for extreme restlessness, shows that the father’s genes promote waking and suckling.
He further stated that babies are most restless during the night for the first six months, which is when mothers are returning to their natural state of fertility.
An anthropologist from the University of Notre Dame, Indian, Dr James J. McKenna, has commented on the article by Professor Haig by stating that there are huge benefits for both mother and baby with breastfeeding. He said that the benefits may surpass the negativity of being awakened constantly throughout the night. He also stated that the wakefulness of the baby may not be an evolutionary strategy to prevent other siblings from being conceived, but simply to remain well-fed and healthy.
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