Washington, April 18 (IANS) An analysis of Spanish skulls spanning about 300 years shows that the difference between the sexes' cranial features shrank over time, a media report said. While both sexes' crania got bigger, women's grew more, decreasing the gender gap, the researchers found.

The findings are expected to help experts tasked with identifying human remains. The conclusion is based on a study of more than 200 crania - the part of the skull that holds the brain, the Christian Science Monitor reported.

The crania contained in two collections, one amassed during the 19th century by a doctor, and one from an excavated cemetery dating back to the 16th through 17th centuries.

There are multiple factors that could explain this change, said lead researcher Ann Ross, an anthropologist at North Carolina State University.

These include changes in nutrition, living conditions and genetic influences on the populations from which the skulls came. The researchers also compared the features of the Spanish crania with a collection from 19th-century Portugal.

The findings would helpful forensic anthropologists who are asked to identify human remains and need to be able to reliably distinguish between males and females, the monitor said.

The researchers also looked at differences in the bone structure, such as changes to the teeth sockets, and found that some changes had occurred over time for both men and women. The study was published in the recent issue of the journal Forensic Science International.