Rhesus monkeys engineered to express a human gene reportedly show delayed brain development and better short-term memory. Fellow scientists are raising ethical red flags.

Humans might also inherit such brain changes, a new study suggests.

The findings highlight the need for long-term monitoring of children exposed to the virus, say scientists. 

The approach, which has never before been successfully attempted in primates, could lead to improved animal models for human biology and disease.

Life at the bottom of the pecking order ramps up inflammation, according to new research, an effect that appears to be reversible.

A round-up of recent discoveries in behavior research

A cytomegalovirus-based vaccine eliminated simian immunodeficiency virus from rhesus macaques, raising hopes of a similarly effective HIV vaccine.

Researchers can see the differences in the neuronal activity of monkeys that use different strategies to reach out to a target.

In rhesus macaques, an individual's drop in the social hierarchy leads to overactive immune genes and, possibly, poor health.