It's amazing how many ways one can find to use excrement! This article discusses how dung helps in the study of ancient history, and how feces can be used to save endangered species.
Many will call today's topic the most unpleasant in the world. Not to mention the subject of the conversation itself. It's about feces.
Man invented many different names for this substance and the process of its "production", mostly allegorical.
But few people think about the fact that feces, or excrement, play a critical role in the system of life on Earth.
This article is about how diverse functions are performed by feces. They have at least five unexpected and very important uses.
Excrement Museum: Everyone wants to talk about faeces
Honestly! Scientists at the Isle of Wight Zoo in the UK have carefully placed twenty stool samples side by side in individual vacuum capsules for zoo visitors to get to know them better.
Samples of excrement of various animals are presented: lions, meerkats, skunks living in the zoo. And along with human babies.
"They all have different sizes, shapes, textures ... This is an inexhaustible storehouse of information, " says museum curator Nigel George.
None of the zoo staff specialize in scatology, but George says that even an ordinary person can tell a lot about an animal by the appearance of feces.
You can immediately understand what animals eat - the waste of crows, for example, contains a lot of undigested bones and chitinous shells of beetles.
"In general, carnivore feces give off a pungent odor than herbivore feces, " adds George.
A sample of herring gull feces can be seen with pieces of plastic - a reminder that the effects of technological progress can be seen even in feces.
The proportion of water in excreta is on average about 75%. Through trial and error, the researchers found a way to "isolate samples so that they do not emit an odor and are generally safe for the public."
This required the creation of a stool drying device. Development took a year. "The setup is simple, but it works, " notes George.
According to him, a long pipe is inserted into the dryer, in which fecal samples are comfortably located on special trays.
Depending on the size of the samples, they are kept in the dryer for different times - from a day to several weeks.
Then they are placed in a transparent resin and a vacuum is created, evacuating any air bubbles.
It turns out something like a crystal ball. The only difference is the turd in the middle of this capsule.
"I think hardly anyone realizes, looking at these balls on the pedestals, how much human labor has been invested in them, " says George.
He says that the public reaction came as a surprise to them: "We noticed that people themselves are surprised by their own reaction. Disgust quickly gives way to curiosity, and people are already resting their noses on the ball, examining what is inside."
George says the concept has spread worldwide since the museum opened in March this year. "It seems that everyone wants to talk about excrement!"
The importance of whale feces for the ocean
Most marine animals feed closer to the surface and defecate in deeper layers of the sea, but whales do the opposite.
That is why, according to Joe Roman, their feces are of particular importance.
"Before finally diving into the depths, the whale that has risen to the surface properly empties its intestines, " - Roman, a biologist at the University of Vermont, USA.
This fecal plume, as it is called, contains many nutrients and enriches surface waters with nitrogen, iron and phosphorus.
"They fertilize the ocean, " Roman concludes. "They bring nutrients to the surface."
This effect is called the whale pump - it has been studied by Joe Roman for the last 10 years.
Once the nutrients are on the surface, they are consumed by fish such as salmon.
These fish, in turn, are eaten by seabirds, which carry nutrients from the sea to the shore, where they are devoured by other land animals, such as bears.
In this sense, as Roman says, "whales play an important role in the mechanism of lifting nutrients from the bottom of the ecosystem."
Roman and his colleagues have already tracked how the pattern of nutrient transport has changed over the course of earth's history.
So, whales appeared about 60 million years ago.
Around this time, one of the groups of land mammals got into the habit of splashing in the river more often than usual - and after some time it developed into a completely aquatic species.
Transformed into whales and dolphins, mammals colonized the ocean.
Whales began to feed on fish and crustaceans and developed the ability to digest chitin, of which the hard shell of a number of mollusks - their so-called exoskeleton - consists.
"Most mammals cannot digest it. Consequently, the microflora in the intestinal tract of a whale is radically different from what we imagined it to be, " he says.
The composition of whale feces depends on the characteristics of the individual and its diet, says Joe Roman.
If a whale feeds on krill, its feces are most often in the form of red or pink clots the size of a human fist.
However, for those whales whose diet consists of fish, the mass of excrement is dark green and more liquid, due to which the fecal cloud spreads to the size of a research vessel, the scientist said.
"This is a massive burst of nutrients at one time. In other words, the results are the same for both options, even if the process is slightly different."
Some living things eat feces - and that's smart!
For most of us, feces are waste that is thrown out of the body as unnecessary, but a number of animals see them as a valuable resource and do not even mind eating them.
"Coprophagous animals squeeze out nutrients from the stool of other animals that they themselves could not extract, " explains Markus Byrne of Witwatersrand University in Johannesburg, South Africa. "There are very few such substances left."
In Australia in the late 1980s, Byrne began studying coprophages, which include dung beetles, fly larvae, and even - oh god! - beautiful butterflies.
“Australia already had 300 of its own species of dung beetles, but they were used to eating kangaroo excrement, not cows, ” he says. “Cow dung is 80% water and comes out in large liquid cakes, while kangaroo excrement is more like small hard balls ".
"Australian dung beetles are not used to this [bovine] material, " continues the scientist. Therefore, for the processing of manure produced by cattle farms, it was decided to bring in those beetles that had time to adapt to it in the course of evolution.
An extremely important biological regulation program has been developed that has been in effect for 20 years.
The dung beetle's brains are about the size of a grain of rice, but these insects are a treasure trove of talent, Byrne says.
They roll manure into balls and steal it where no one else can covet it.
And if you look at how they reproduce and fight for partners, it will be difficult to believe that we are just a small insect, the scientist notes.
For example, males demonstrate their superiority in combat with huge horns. "These crumbs fight as if they were antelope, deer, or caribou!"
In addition, despite their small size, males of this species have larger testicles than many of the larger beetles.
But these handsome men succeeded not only in seducing the fair sex and rolling balls. Their real talent is navigation.
"They look at the sky and navigate by it, " says Byrne.
People in such cases use a map, but the beetle can see the polarization of light, which we do not see, and is better at distinguishing shades and degrees of brightness.
Byrne proved that one of the species uses the Milky Way as a reference point, thanks to which it successfully rolls its dung balls at night.
"It's breathtaking. Just think: a stupid little beetle is peering into the distant corners of our galaxy, " he says.
Ancient horse dung - the key to ancient history
For those who are not friends with ancient history (as your humble servant), we recall that Hannibal is a commander who led the army of Carthage during the war with Rome, which lasted from 218 to 201 BC. e.
Hannibal is considered one of the greatest military leaders in history, and archaeologists have long sought to figure out in detail how his army moved during that 16-year war.
However, one episode - the passage of Hannibal's army across the Alps with 15, 000 horses (and several war elephants) - remains a mystery.
Some suggest that Hannibal crossed the Alps (making his way from present-day France to Italy) through the Col de la Traversette, located at an altitude of 3 thousand meters above sea level.
"A lot of evidence indirectly indicates that he used this particular pass, but no one found scientific evidence - nothing that could be verified, " says Chris Allen, a microbiologist ecologist at Queen's University in Belfast, UK.
For two thousand years, historians, politicians, scientists and even Napoleon fought over this mystery. However, soon it will probably be unraveled - thanks to a hefty pile of dung.
"A two-day parking lot with 15-20 thousand horses - you can be sure it will not pass without a trace, " says Allen, nicknamed the "dung scientist" by the local press.
Not far from the Col de la Traversette, Allen's group, along with fellow archaeologists, found a hole in an area the size of a football field. After conducting genetic analysis and studying the local environment, the group discovered massive deposits of animal excrement.
Samples were taken at 5 cm intervals to a depth of 70 cm - enough to penetrate the soil horizon, which formed 2, 200 years ago, during the lifetime of Hannibal.
"From this layer, something very concrete happened about 2, 180 years ago, " says Allen. "The elements of interest were scattered over a large area."
The removed layer of soil contained a lot of ancient horse manure, radiocarbon dating of which suggests that it could have been produced 200 BC. e. - which is very close to 218 BC. BC, in which Hannibal is believed to have crossed the Alps.
The samples were found to contain many Clostridia bacteria, which are often found in horse feces.
"Clostridia was in 12% of the samples, and it is dated to that period. At the date we need, the concentration becomes six times higher, " says Allen, adding that this find is a real "genetic letter to the future."
These and some other observations allow "to say with confidence that a large number of mammals passed here 2200 years ago, leaving a certain trace."
So far, archeology hasn't paid any significant attention to faeces, Allen says. But if archaeologists begin to collaborate more often with "dung scientists", who knows what they will be able to discover ...
Feces Trained Snoopers to Watch for Endangered Species
From seasoned bloodhounds tracking criminals to bloodhounds at airports, dogs are second to none in scent searches.
"A robot capable of detecting odors will never replace a dog, " says Robert John Young, a wildlife biologist at the University of Salford in the UK.
"The dog's nose is too subtle. But even if such a robot does appear, it still won't be able to survey the situation as quickly. Plus, it's cheaper to keep dogs."
Some unlucky puppies are trained to smell feces. They help conservationists find animal excrement in the wild faster.
Such findings make it possible to clarify the habitat of populations and, at the same time, their diet.
"It is not the breed of the dog that is important here, but its character, " says Samantha Bremner-Harrison of Nottingham Trent University in the UK.
According to Samantha, you can safely take a pet from a shelter - as a rule, such dogs are very energetic and respond well to encouragement.
After working with Californian breeders, whose charges she trained to look for excrement, Samantha is now planning to open similar courses in Nottingham.
“The thing about our profession is that we are constantly looking for faeces, as they are a source of important biological information, ” says Robert John Young, who has to keep samples of feces from Brazilian monkeys in his refrigerator.
25 years ago, when Young was just starting his career as a biologist, students had to examine feces under a microscope to understand what the animal ate.
"Now that we have new tests and online genetic analysis tools at our disposal, things are moving faster."
To assess the level of stress of an animal (in particular, to understand how much ecotourists annoy it), it is enough to examine its feces for hormones. Sex hormone monitoring helps track ovulation in females.
“This has allowed us to increase the population of reddish monkeys, one of the endangered primate species in South America, ” Young says.
Scientists also use animal stool samples to determine the DNA sequence.
By putting excrement on a special kind of filter paper used in DNA analysis, we can determine if there is a genetic link between two groups of gorillas separated by a mountain range, Young explains.
In turn, within promiscuous species, we will understand who is the father of the offspring and who has what genes.
"Give me a piece of monkey poop and I'll tell you if she's color blind, " Young assures.
There are many ways to regulate animal behavior through their own bowel movements.
For example, environmentalists from the San Diego Zoo decided to transport the black rhinoceros, which lives in South Africa, to an area where there are fewer poachers.
It can be difficult to carry out such an undertaking, since rhinos are very territorial animals, and the appearance of an intruder can provoke aggression.
However, conservationists can use the rhinos' tendency to actively mark their territory to set the stage for newcomers to settle in.
They take stool samples from individuals they plan to add, and here and there mark the territory of their new place of residence.
When rhinos are launched into their habitat a few weeks later, the old-timers are in fact already familiar with them.
"After a couple of weeks, the rhinos kind of say to each other, 'Oh, this is Fred, we know him, " Young says.
In general, no one doubts that excrement is primarily waste. But for science and many animals, they mean something.