A study by a team of researchers from Singapore, Australia, Switzerland, Britain and the United States led by NUS scientist Luke Gibson found primary forests, old-growth forests suffering the least disturbance, sustain the highest levels of biodiversity and are vital to many tropical species.
Logging and agricultural expansion have altered the world's tropical forests, leaving few primary forests untouched by humans, and the biodiversity capacity of rapidly expanding degraded and converted forest landscapes is hotly debated.
"Some scientists have recently argued that degraded tropical forests support high levels of biodiversity," Gibson said in an NSU release. "Our study demonstrates that this is rarely the case."
Analyzing studies of 28 tropical forests, the researchers compared biodiversity in primary forests to that in regenerating forests and forests degraded by logging and converted to agriculture.
Overall, biodiversity values were substantially lower in disturbed forests, they said.
"There's no substitute for primary forests," Gibson said. "All major forms of disturbance invariably reduce biodiversity in tropical forests."