Why doing good also makes us feel good, during the holidays and beyond

The holiday season is a time for giving thanks, giving gifts — and for many, a time for giving back.

Food banks, services that deliver meals to seniors and other U.S. charities typically see a surge in volunteering between Thanksgiving and the end of the year. But there are good reasons to volunteer at any time of the year.

Alfred Del Grosso volunteers weekly to work the lunch shift at Shepherd's Table, a food bank in Silver Spring, Maryland. "I feel more connected to the broader community," he said.

Most Thursdays, the retired chemist from Kensington, Maryland, also lends an unpaid hand to help clear fallen trees and brush from local trails with the Potomac Appalachian Trail Club. "It's mostly volunteers who help maintain the trails," he said.

Researchers who study human evolution and