New! Sign up for our free email newsletter.
Reference Terms
from Wikipedia, the free encyclopedia

Rhesus Macaque

The Rhesus Macaque (Macaca mulatta), often called the Rhesus Monkey, is one of the best known species of Old World monkeys. It is a typical macaque, common throughout Afghanistan to northern India and southern China. Rhesus Macaques are sexually dimorphic. Adult male Rhesus Macaques measure approximately 53 centimeters on average and weigh an average of 7.7 kilograms. Females are smaller, averaging 47 centimeters in length and 5.3 kilograms in weight. They are brown or grey in color and have pink faces which are typically bereft of fur. Their tails are of medium length and average between 20.7 and 22.9 centimeters. They typically have a lifespan of about 25 years. The Rhesus Macaque is well known to science owing to its relatively easy upkeep in captivity, and has been used extensively in medical and biological research.

Related Stories
 


Health & Medicine News

March 23, 2026

Scientists have uncovered a hidden “death switch” in the brain that may be driving Alzheimer’s disease—and even found a way to turn it off in mice. The culprit is a toxic pairing of two proteins that, when combined, triggers the destruction ...
A new blood test could change the outlook for one of the deadliest cancers—pancreatic cancer—by catching it much earlier than ever before. Researchers identified two previously unknown proteins in the blood that, when combined with existing ...
A surprising new study reveals that blocking a supposedly protective enzyme, Caspase-2, could actually backfire—raising the risk of chronic liver damage and cancer over time. Researchers found that without this enzyme, liver cells grow abnormally ...
Scientists have uncovered a surprising brain-based trigger for high blood pressure, tracing it to a small region in the brainstem that normally controls breathing. This area, which kicks in during forceful exhalations like coughing, laughing, or ...
GLP-1 medications like semaglutide (Ozempic) may offer unexpected mental health benefits alongside weight loss. A large study found major drops in depression, anxiety, and psychiatric-related hospital visits among users. Even substance use disorders ...
Antibiotics are accumulating in a major Brazilian river, especially during the dry season when pollution becomes more concentrated. Scientists even detected a banned drug inside fish sold for food, raising concerns about human exposure. A common ...
A new pill, enlicitide, reduced LDL (“bad”) cholesterol by about 60% in a large clinical trial, matching the power of injectable therapies. Because it’s taken orally, it could overcome one of the biggest barriers keeping patients from using ...
Researchers have discovered that cancer spread isn’t random—it follows a kind of biological “program.” By studying colon tumor cells, they identified gene patterns that signal whether a cancer is likely to metastasize. Their AI model, ...
Scientists have engineered probiotic bacteria to act as tumor-seeking drug factories. In mice, these bacteria infiltrated tumors and produced a cancer-fighting drug right where it was needed. This targeted approach could make treatments more ...
“Forever chemicals” may be affecting kids in ways that last a lifetime. A new study links early PFAS exposure to lower bone density during the teen years, especially in girls. Researchers also found that when exposure happens may play a key ...
Aging men often lose the Y chromosome in a growing number of their cells—and it may be far more dangerous than once believed. This loss has been linked to heart disease, cancer, Alzheimer’s, and shorter lifespans. Researchers suspect Y-less ...
The largest review of medicinal cannabis to date found it doesn’t effectively treat anxiety, depression, or PTSD—despite millions using it for those reasons. Researchers warn it could even make mental health worse, raising risks like psychosis ...

Latest Headlines

updated 12:56 pm ET