By Susan Milius
From Bloomington, Ind., at a meeting of the Animal Behavior Society
![](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2002/08/1473.jpg?resize=105%2C150&ssl=1)
Genetic analysis of white-tailed deer in a Michigan reserve has turned up what may be the first documentation of more than one father per twin litter in a big, free-ranging hoofed mammal.
Several dads siring offspring in the same litter wouldn’t be a surprise for small mammals such as ground squirrels, says Anna Bess Sorin, now at the University of Memphis in Tennessee. Only one previous genetic analysis of large ungulates, in this case, deer held in a farm pen, has ever shown evidence of more than one dad.