Spider Monkeys Seen Walking Upright in Mexico’s Mangroves

Puerto Morelos, Quintana Roo — The National Commission of Natural Protected Areas in Mexico (CONANP) has released a video showing two spider monkeys (Ateles geoffroyi) walking upright on two legs in the Mangrove Flora and Fauna Protection Area of Puerto Morelos, Quintana Roo.

The footage, captured during biological monitoring conducted in collaboration with El Colegio de la Frontera Sur, has sparked intrigue among researchers and the public alike.

A Rare Display of Bipedalism

Bipedalism—walking on two legs—is a trait most commonly associated with humans and their evolutionary ancestors. While some primates occasionally stand or walk upright, sustained bipedal movement is rare among non-human species.

The video, shared by CONANP on social media, shows the spider monkeys moving steadily on their hind legs through the mangrove habitat. The commission accompanied the post with the caption: “Have you ever seen a spider monkey walking on two legs? This video was made possible thanks to the biological monitoring we conduct in collaboration with @ecosurmx in the Mangrove Protection Area of #PuertoMorelos.”

Theories Behind Bipedalism in Primates

The origins of bipedalism in primates remain a subject of scientific debate. Most theories suggest that walking upright evolved as an adaptation for terrestrial movement, offering advantages such as energy efficiency, improved visibility over tall grass, and the ability to carry objects or use tools.

However, the behavior observed in these spider monkeys challenges some assumptions, as the species is primarily arboreal. Their anatomy—including long limbs, mobile shoulders, and curved fingers—is adapted for life in the trees, making their bipedal locomotion particularly unusual.

Conservation and Monitoring Efforts

The Mangrove Flora and Fauna Protection Area in Puerto Morelos is a critical habitat for biodiversity, and ongoing monitoring by CONANP and research partners helps track wildlife behavior and ecological health.

This discovery follows recent reports of illegal wildlife trafficking involving spider monkeys in Mexico, including an incident in Tabasco where authorities detained two individuals in possession of nine spider monkey infants.

Scientific and Public Interest

The footage has drawn attention not only for its scientific implications but also for its rarity. While spider monkeys are known for their agility and intelligence, sustained bipedal movement had not been widely documented in the species before this observation.

Researchers continue to analyze the behavior to determine whether it represents an isolated incident or a more common but previously unrecorded trait among spider monkeys in the region.

For now, the video stands as a striking example of the complexities of primate behavior and the ongoing discoveries within Mexico’s protected natural areas.