Why is there shit in its head?

Scientists have seen animal skulls and feces.

But when feces appeared in the animal skulls, they couldn't help getting excited.

When scientists found it on the coast of Maryland, it was already fossilized.

If there is any difference between this little fish and other fossilized animals, it is that its brain is full of feces.

Scientists have never seen anything like this before.

But they are quite sure that the droppings in the little fish's brain are not its own.

So the question is, who is the owner of the feces, and why is its excrement in the skull of a fish?

Fish is a restaurant and a toilet.

This small fish comes from the family Phaeocephalidae, a species called Astroscopus countermani.

The reason for the reputation of "looking at the stars" is that both eyes grow on the top of the head, as if you don't have to look up to see the stars.

But now the species is extinct.

The small fish was found on the coast of Maryland in the United States.

There, the Calvert cliff (Calvert Cliffs), which stretches for 35 miles (more than 50 kilometers), has historically been rich in paleontological fossils.

Dr. Stephen Godfrey (Stephen Godfrey) from the Calvert Marine Museum is a curator and researcher in the field of paleontology.

Instead of destroying the fish's skull, he and his colleagues used spectral equipment to image the skull.

As a result, the team found a dense array of tiny particles, each about 1-5 mm long and 0.4-2 mm wide, where the brain was originally located, and the aspect ratio was always close to 2:1, uniform in shape and size.

Although this is the first time scientists have seen such a scene in a skull, they do have an impression of similar particles and arrangement.

Because, also on the Calvert cliff, they also found some mineral clumps, and the small particles on it were feces.

More precisely, it is already a faecal fossil (coprolite).

Fecal fossils are different from ancient feces (paleofeces).

Ancient feces retain a lot of organic components; by contrast, the main components of fecal fossils are usually inorganic salts, such as phosphates, silicates, carbonates, etc., especially calcium phosphate.

According to Dr. Godfrey, spectral analysis shows that the particles in the head bones of small fish contain higher concentrations of calcium and phosphate, which are common components of fecal fossils.

Coupled with the recognizable shape of the particles, scientists believe it is the feces that invade the brains of the fish.

So, who left the faeces behind the team speculated that there might be scavengers who crawled into the fish's head after it died and excreted its feces.

The suspect whose skull is only a few centimeters wide and can leave tiny fecal particles in such a narrow space may be a petite and soft invertebrate, such as some kind of worm.

Millions of years ago, such small animals might have nibbled on decaying meat at the head of the fish, leaving small oval droppings there.

Although each grain of feces is small, it adds up.

By the time it was finished, hundreds of droppings had probably filled the fish's brain, replacing the fish's brain.

Over the years, scientists have almost always felt the existence of this scavenger from fecal fossils.

Fossils such as feces or footprints that record biological activity (rather than the remains themselves) are called "trace fossils", and many scientists classify and name creatures they have never met based on the clues.

But in any case, that little fish will be remembered by many people as "the first known vertebrate with shit in its brain".

Traces of a dung eater.

The skulls of the small fish are well preserved and full of feces are well preserved.

This is rare, and it also means that after scavengers fill the heads of fish with feces, there may be no next round of animals to eat in the head of small fish.

In this way, feces will not be eaten.

Not really.

In addition to the tiny fecal particles above, scientists have found larger fossilized faeces in this area of the Calvert cliff.

As trace fossils, these faeces not only reflect the fact that its owner once existed, but also show the traces of other animals visiting.

For example, a fossilized piece of dung can be up to 178 millimeters (nearly 20 centimeters) long, but it is curved at an angle of about 90 degrees.

At the turn, there is a hole with a diameter of about 15 mm.

If you open it, you will know that the hole is a space similar to a cylinder, with little change in width, and there are bends and forks in the depths.

Not only that, there are also small traces that have been dug on the walls of the cave and on the surface of fossilized dung.

Based on the size of the faecal fossils, the team thinks it may belong to a Miocene crocodile, from an extinct genus (Thecachampsa), because fossilized crocodiles of this genus have been found nearby.

However, the wide "tunnel" is unique and rare in fossilized dung found in the past, which scientists believe was dug by some unknown animal.

So, the biggest suspects are some dung-eaters, such as the dung beetles we are familiar with, or some dung-eating flies, and so on.

Of course, there may also be some kind of animal that digs holes in its droppings to create living space for itself.

This will have to wait for future scientists to study more fecal fossils and dig out a more conclusive truth.

The root of all evil.

Looking at this, you may wonder when scientists began to study fecal fossils.

In 1824, a fossil hunter named Mary Anning discovered a strange object in the belly of the ichthyosaur skeleton and called it "bezoar stone".

In 1829, geologist William William Buckland suggested that the fossilized objects were actually animal droppings.

Everything begins from then on.