The 3 months of biparental care of their single
altricial chick is followed by 9-14 months of uniparental care by the mother (Diamond, 1972, 1973; osorno, 1999; Osorno and Szekely, 2004).
They probably have evolved from the parental care relationship (i.e., feeding and cleansing of the young), which is obligatory in mammals (and among birds with
altricial young), and are particularly suited for group cohesion.
The latter has "precocial" characteristics for development, such as long life, large brain and small offspring, but they are quite defenseless as compared to the standard "
altricial".
Since during the first two weeks of life it is not possible to isolate
altricial pups of C.
the need to support an
altricial (completely helpless) newborn may even have contributed to the evolution of bipedalism (walking on two legs)," says Katherine Dettwyler, PhD., a professor of anthropology at the University of Delaware.
What, in the bird and animal worlds, are the meanings of the opposing terms
altricial and precocial?
More commonly the young are delivered
altricial. They are born with their eyes and ears closed and have no visible hair growth.
Altricial (ahl-trish-ahl) Young that are very dependent after birth; kittens are
altricial.
ANSWERS: 1 Whitechapel; 2
Altricial means being born dependent on its parents; precocial being immediately self-sufficient; 3 A.S.
The
altricial mammals (those born immature, e.g., rat, cat, human) have much higher amounts of REM sleep at birth and during the early years of development as compared to that present during adult stages (28).