Page 102 - Devotion Among Animals Revealing the Work of God
P. 102
Many animal species show their devotion when their young need to eat. For
instance the great tit makes hundreds of flights every day to feed its young.
The seal loses much weight when nursing its pups.
Female mammals have an additional problem to deal with:
They can feed their young only by suckling them. In this lactation
period, they need to increase their food intake substantially. For in-
stance, seals suckle their young for between 17 and 18 days after
they give birth to them. The young gain much weight over this time,
whereas the mothers will lose much, because they do not feed dur-
ing this time. 97
Parents that must care for their offspring use three to four times
98
the energy they expend at other times.
To determine the "cost" to parents of raising their young, biolo-
gist Heinz Richner and his students at the University of Lausanne
made an experiment with the great tit—which revealed the difficul-
ties of being a father. During this experiment, Richner frequently
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