But even an error could work in the animals' favor. The scientists think protecting all fawns, and not just their own, helps the deer maintain a strong, near delay-free fight or flight response.
Their findings have been accepted for publication in the journal Animal Behavior.
The researchers explained that "a female's ability to defend her own offspring hinges on an overriding motivation to respond aggressively as soon as she hears distress calls."
Since fawns only utter these calls "when capture is imminent," a delay of just a few seconds could have fatal consequences.
Another possible explanation could be that the deer simply benefit by banding together in groups regardless of species. More mothers on fawn-guard increases the chances that a coyote will leave all of the young alone.
"The care of young by mammal mothers is probably based on intense emotions," said Nigel Barber, author of the book "Kindness in a Cruel World."
While these feelings are usually directed toward kin, Barber added that there are many examples, aside from deer, of female animals who protect and care for the offspring of others. Birds, bees, and numerous other mammals — including humans — do it too.
