In this photo from 1914, French soldiers can be seen learning to work with a sentry dog. These brave canine soldiers were invaluable assets in the field for spotting enemies, thanks to their ...

All tree leaves have an outer layer called the epidermis, which can also be used in the identification process. This leaf "skin" always has a waxy cover called the cuticle and varies in thickness ...

Marlon Brando is widely acknowledged to be the greatest movie actor of all time. Anyone could imitate Marlon Brando — it was as simple as a scowl, a nasal voice and a scratch of the cheek — but few ...