Look: Scientists finally discover how boa constrictors can eat giant meals without suffocating

Inhale, Exhale by Jennifer Walter Updated: Feb. 20, 2024 Originally Published: March 24, 2022 Henrik Sorensen/DigitalVision/Getty Images

Henrik Sorensen/DigitalVision/Getty Images The boa constrictor may be non-venomous, but the 10-foot-long snake is known for its lethality in other ways.

Boas are known to wrap their thick bodies around animals and squeeze them to death. Then, they swallow their prey whole — fur, skin, bones, and all — and let their digestive systems do the work. Joe McDonald/The Image Bank/Getty Images

Mark Lui But their ability to devour carcasses whole puts extreme strain on the snakes’ ability to breathe. Their stomachs press against their lungs, making it difficult to expand their ribcages and suck in air after a big meal.

Shutterstock Researchers set out to answer the question of how boa constrictors can kill and eat without suffocating in a study published Thursday the Journal of Experimental Biology.

Henrik Sorensen/DigitalVision/Getty Images “When you kill something really big [and eat it], you fill yourself up in this immense way. You’re completely full to the gills , literally.” John Capano, organismal biologist and study co-author, tells Inverse.

For the study, the researchers recruited several boa constrictors and took X-rays of their bodies under different conditions.

Mark Lui The snakes were fitted with a blood pressure cuff around a section of their bodies to mimic the squeeze of a big meal or the act of constriction.

When one part of the boa’s rib cage is restricted (right), it can still use another part to continue breathing (left).

Even when the boa’s rib movement is restricted while resting on a table, it can expand and contract its lungs in the suspended areas.

Scott Boback and John Capano

Fernando Trabanco Fotograf��a/Moment Open/Getty Images The researchers learned that the snakes are able to alternate which part of the ribs they expand to breathe during different activities, an act known as modular ventilation.

This diagram shows the different parts of the ribs that the boa will expand when doing different activities.

This ability was likely an important part of the snake’s evolution, helping it adapt to hunt down large prey and be able to digest it without cutting off airflow.

ZU_09/DigitalVision Vectors/Getty Images

Combined with constriction and extremely flexible jaws, modular ventilation adds to the adaptations that make the boa a fearsome predator.

Capano says it’s unclear when these traits evolved, but likely that they developed in tandem, building off of each other. Shutterstock

Shutterstock “I think that [these traits] all kind of evolved in concert. They were all probably extant in some form, and then just kind of kept growing over time.” Capano tells Inverse.

Shutterstock Read more about this study here .