Washington, July 23 - Ancient Mayans can teach us a thing or two about nature conservation, says a recent study.

'From our research we have learned that the Mayans were deliberately conserving forest resources,' said David Lentz, professor of biological sciences at the University of Cincinnati (U-C).

'Forty years ago the emphasis was on what king built what palace, who slew whom and who is portrayed on what stele. It's all about the rulers and their exploits,' said Lentz.

'They didn't look at the economy, agricultural practices, forest management or how the people and the culture functioned,' he added.

And what the U-C team has learned by studying these processes is that the Maya, at least initially, were practising good forestry management.

The U-C team is the first to be permitted to work at the Tikal site core in northern Guatemala in more than 40 years. Previous excavations reflected an interest in culture and history, but interests are different in the 21st century.

'They (Mayans) were not allowed to cut down what we're calling the 'sacred groves',' said Lentz. 'Then that changed during the Late Classic period with Jasaw Chan K'awiil -- one of the greatest figures of pre-history.'

After that, the Maya rebuilt the city of Tikal in a way never seen before.