For better science, give lab primates companions

An increasing number of medical labs are housing primates in cages with other monkeys, reports NPR. This is part of an effort to improve living conditions for lab animals.

Why it matters: Companionship benefits both the primates and the research:

• "Social housing is the most important thing to a primate," Kathleen Conlee of the Humane Society of the United States told NPR. When primates are isolated, she explains, they "go crazy" and pull out their hair, scratch and bite themselves.
• Kelly Metcalf, who studies HIV in monkeys at Johns Hopkins University, tells NPR her data is better since the animals were placed in social housing because lonely monkeys have weaker immune systems.

The numbers: In 2016, there were 109,821 primates in labs in the US. In 2003, 59% of primates were kept alone in cages. In 2014, that number has decreased to 35%.Improvements vary by species. About half of rhesus macaques still live in cages alone.Read more about the legalities of primate research and the social conditions animals are raised and kept under in Nell Greenfieldboyce's piece at NPR.