Duck bill’s sensitive touch develops in the egg
The bills of even newly hatched ducks might be as sensitive as our hands, as touch sensors in their beaks are as abundant as those in our fingertips and palms. That’s the take-away of new research published today in the Proceedings of the National Academy of Sciences that describes the origins of touchiness in the common duck’s quacker. Researchers knew that duckbills can sense light touch but have muted responsiveness to temperature. This comes in handy (or bill-y) since the birds forage for food in cold, murky bottom waters. Now, researchers find the sensors duckbills use to perceive touch work even before hatching. That likely helps young ducklings scavenge for food alongside adults soon after birth. In keeping with the need to feel for food, the ducks have more nerve cells to relay touch signals than chickens, which rely on eyesight to find sustenance, they report. That means different developmental programs are at work in ducks and chickens, which could help scientists uncover how touch evolved. Because the duck’s touch sensors are similar to mammals’ and their bills aren’t covered in fur, the authors suggest embryonic duckbills might be a better model than standard laboratory rodents to study touch sensation as it applies to us relatively hairless humans.