Original photo by FatCamera/ iStock
Even if you’ve never heard of a foramen ovale, you probably had one at one point in your life. It's the name given to the small opening between the upper heart chambers that forms as a baby grows in the womb and usually closes within the first few weeks of infancy.
Once a baby is born, the pressure caused by blood pumping through the heart usually closes the foramen ovale on its own. When it doesn’t close, it’s known as a patent foramen ovale (PFO) and usually has no ill effects; about 25% of the population have a PFO, most of whom don’t even know it.
The heart has four chambers — two atria on top and two ventricles below — and though no one’s sure what causes patent foramen ovale, genetics are assumed to play a role. The biology of infants is wonderfully weird in other ways as well. Babies are born with nearly 100 more bones than adults — about 300, whereas grownups have 206. Many of those excess bones are actually made of cartilage and fuse together throughout childhood.
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The ______ has the largest heart of any living creature.
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“Infant” comes from a Latin word meaning “unable to speak.”
We tend to think of the word “infant” as simply meaning a very young baby, with most people considering infancy to end at 1 year old. The word’s etymology is more specific, however: “Infant” comes from the Latin word infans, which means “unable to speak” or “incapable of speech.”
The Latin term has been in use since at least the 14th century, with “in-” meaning “not, opposite of” and “fans” meaning “to speak.” The word used to refer to children as old as 7, but its scope has since narrowed to our current definition.
Michael Nordine is a writer and editor living in Denver. A native Angeleno, he has two cats and wishes he had more.
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