Spanning The Globe September 2025
- marketingc8
- 1 day ago
- 4 min read
It’s time to go spanning the globe for anatomy news and notes!
Grand Hot Spot
We love this article on History.com about how the Grand Canyon was once a hotbed for evolution. Two billion years old, the canyon “played a crucial role in what’s known as the Cambrian explosion, which started around 530 million years ago and last about 40 million years.”
According to the article, “nearly all the major groups of animals alive today can trace their evolutionary origins back to the Cambrian period.” As hard as it is to imagine, the Grand Canyon at that time was underwater and “teeming with rapidly evolving sea organisms.”
Apparently the ancient shoreline, the article noted, offered “prime conditions” for life. The ecosystem’s warm waters “were neither too deep nor too shallow, creating a sweet spot environment for life to thrive and evolve.”
By comparison to this activity, the Grand Canyon itself is only 5 to 6 million years old. And if you’ve ever hiked from the rim to the river and back (we have—it’s a long way, especially up!) it’s hard to believe the dry environment was once “teeming” with anything. One thing we do know, when you think about these kinds of changes over hundreds of millions of years, you need to bring an active imagination.
It Takes Guts
The human gut is the site of rapid change. That’s the headline from research conducted by a group of international researchers and reported in Science. In fact, there have been recent and important deviations from other mammals, including the chimpanzee.
Scientists from Switzerland, Michigan, and North Carolina worked together to use stem cells to create human, chimp, and mouse intestinal “organoids.” An organoid is “an artificially grown mass of cells or tissues that resembles an organ.”
The tiny models built by the researchers of the intestines offered an “unprecedented glimpse” into the development of the small intestine, reported this article in Phys.org. The scientists found that human gut epithelial genes “contained signs of recent evolutionary change, including one for an enzyme responsible for the digestion of lactose in milk as well as differences in the expression of genes associated with immunity, lipid metabolism and cholesterol absorption.”
The group focused on something called enterocytes. These are cells that specialize in nutrient absorption and barrier function. These cells have undergone a transformation in humans and this is important “because areas of the human genome that have rapid change influence disease risk and are associated with metabolic and gastrointestinal disorders.”
The work also offered “previously unknown” insight into human-specific alleles. (An allele is a particular version or variant of a gene that determines a specific genetic trait, such as eye color or blood type.) The research is demonstrating how these alleles “may have primed the human intestine to more effectively absorb nutrients.”
Fun fact: The human body contains over 200 distinct cell types, each with a unique structure, function, and role in forming tissues and organs.
The Eyes Have It
How do snails do it? Specifically, the golden apple snail. It can regenerate a missing or damaged eye. Pretty cool, we say. And even more importantly, the eye of the golden apple snail is “fundamentally similar” to the human eye, according to this article in Eureka Alert.
Alice Accorsi, an assistant professor of molecular and cellular biology at the University of California, Davis, studies this particular kind of snail and this particular talent, with the goal of eventually helping to restore vision in people with eye injuries.
The key? It’s to editing the apple snail’s genome in order to “explore the genetic and molecular mechanisms behind eye regeneration.”
The apple snails, by the way, are from a family of large freshwater snails called Ampullariidae. The golden apple snail, from South America, is Pomacea canaliculate. They are acquatic gastropod mollusks. They have a gill and an operculum. They’re amphibious. And they are considered gonochoristic, meaning that each individual organism is either male or female.
In addition to being easy to grow in the lab, apple snails have “camera-type” eyes — the same type as humans.
The ability of these snails to regenerate their eyes have been known for a long time. In 1766, a researcher noted that decapitated garden snails could regrow their entire heads. However, assistant professor Accorsi, the article notes, is the first to leverage this feature in regenerative research.
According to the article, the researchers already know that the process for these snails takes about a month and consists of several phases. The wound heals, cells migrate to the area, and then those cells specialize and begin to form eye structures including the lens and retina. By the fifteenth day (and here, we need a few !!!) all of the eye’s structures are present, including the optic nerve. A couple more weeks are needed for the structures to mature and grow.
Whoa! We’re amazed. And we wonder: when the snail gets injured does it think, “oh, no big deal. I’ll get vision back in that eye in a few weeks.” Or does it wake up one morning when it’s all back and working and think, “well, cool—glad that’s fixed!”
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