The person is Madeleine Cuff.
The monkeys are brown.
Pacheco is a person.
The primate species are spending more time on the forest floor as they seek refuge from rising temperatures.
The shift from arboreal lifestyles is a sign that the primate are struggling to survive in forests damaged by human activity and climate change, according to scientists.
More than 150,000 hours of observations of 47 tree-dwelling primate species were used in the study.
Howler monkeys and bamboo lemurs are spending more time on the ground in areas where their forest is degraded.
Giuseppe Donati is a member of the study team at Oxford Brookes University.
The animals are being forced to the ground to get shade and water because of the rising temperatures.
Humans log the forest in most tropical countries. The canopy of the forest is opened up by this. That makes the temperature go up.
Climate change is helping to force primate to the ground.
Lesser bamboo lemurs are grazed.
Tim Eppley is a man.
Donati has seen how bamboo lemurs are spending less time on the ground.
He says that bamboo lemurs are tree-dwelling. In the south of the island, bamboo lemurs are able to get out of the forest and go for a walk.
The study found that species that live in large groups and those that don't eat fruit are more likely to spend more time on the forest floor.
These more flexible species may be able to partially adapt their lifestyles in response to climate change and habitat loss.
The San Diego Zoo Wildlife Alliance is a non-profit organisation based in California.
None of the species we studied are likely to transition to a land lifestyle. He says that it isn't a viable long-term outcome to happen in such a short period of time.
The forest habitat that we currently have needs to be protected.
There is a journal reference in the Pnas.
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