Welcome to the second installment of Wingtrip’s Natural History Lexicon, a vocabularly rundown of important words in the world of natural history study. To find future posts on this subject, simply search “natural history lexicon” or find it in the tags. Thanks for reading!
-(of a young bird or other animal) hatched or born in an advanced state and able to feed itself almost immediately.
-(of a particular species) having precocial young.
You probably recognize the etymology of this term. Precocious is an adjective used to describe youthful maturity in humans. Birds, which are the species that typically are described by this term are considered precocial because many bird species span a continuum in the maturity of their newly hatched young. At one end we have the precocial, hatched with eyes open, fully feathered, even able to move about and find their own food within hours of emerging from the shell, (the absolute extreme are a few species that literally walk away from their hatchlings, which are fully on their own at “birth”). On the other extreme we have the altricial (meaning “requiring nourishment), hatching with eyes closed and completely unfeathered, essentially helpless in the nest. These strategies often relate to the life history of the species in question. Many precocial species hatch in an open nest, on or near the ground (ducks and chickens are a common example). Precociality is considered a more primitive trait in birds, because more advanced nests like excavated cavities or woven nests typically hold altricial young.
The continuum between these two reproductive strategies is not a clearly defined line. An example of this being the Common Nighthawk hatchlings in the photo above. They are considered semi-precocious, with mostly open eyes and feathers upon hatching but requiring more help from their parents because they aren’t as mobile as some precocial young; in particular they need to be fed.
This bit of vocabulary can be turned in our direction. Humans are solidly altricial at birth.