Skip to comments.Bears that eat human ‘junk food’ may hibernate less
Posted on 05/14/2019 4:44:33 PM PDT by SJackson
And that might risk their aging faster at the cellular level, a study concludes
Mama bears may need to raise their snouts and join the chorus protesting junk food.
Bears are scavengers. And theyll eat human food when its available. But in a new study, the more sugary, highly processed foods that 30 female black bears ate, the less time those bears were likely to spend hibernating. In turn, bears that hibernated less tended to score worse on a test for aging at the cellular level.
Researchers published the findings February 21 in Scientific Reports. Explainer: How brief can hibernation be?
The new research grew out of an earlier project to see what wild black bears across Colorado were eating, says Jonathan Pauli. Hes a community ecologist at the University of WisconsinMadison.
While a Ph.D. student at the school, wildlife ecologist Rebecca Kirby checked diets from hundreds of bears across the state. Hunters there are not allowed to set out bear bait, such as heaps of doughnuts or candy. That means the animals exposure to human food comes mostly from scavenging.
When bears eat more processed foods, their tissues pick up higher levels of a stable form of carbon known as carbon-13. It comes from plants such as corn and cane sugar. (These farmed plants concentrate the airs normally sparse amounts of carbon-13 as they build sugar molecules. This is different from what happens in most wild plants in North America.)
The researchers looked for the telltale forms of carbon in an earlier study. They found bears in some places scavenging a really high share of peoples leftovers. Sometimes, these leftovers could make up more than 30 percent of a bears diets, Pauli notes.
In the new study, Kirby looked at the impact of diet on hibernation. Bears typically slumber four to six months, during which female bears give birth. Kirby and her colleagues focused on 30 free-roaming females around Durango, Colo. These bears were monitored by the states parks and wildlife department. The team first tested bears for carbon-13. They found that the ones that ate more human-related foods tended to hibernate for shorter periods. Signs of age
Studies in smaller mammals hint that hibernations might delay aging. If true, shortening these seasonal slumbers might have a downside for the bears.
To measure aging, the researchers tested for relative changes in length of telomeres (TEL-oh-meers). These repeating bits of DNA form the ends of chromosomes in complex cells. As cells divide over time, telomere bits can fail to get copied. Telomeres can thus gradually shorten. Some researchers have proposed that tracking this shortening can reveal how quickly a creature is aging.
In the new study, bears that hibernated for shorter periods tended to have telomeres that shortened more quickly than those of other bears. This suggests the animals were aging faster, the team says.
Free-ranging bears didnt always cooperate with Kirbys needs for several kinds of data. And so she does not claim to have made a direct and definitive link between what bears eat and aging. So far, Kirby (who now works for the U.S. Fish and Wildlife Service in Sacramento, Calif.) calls the evidence suggestive.
Using additional methods to measure telomeres could help clarify what is going on at the level of cells, says Jerry Shay. This telomere researcher works at the University of Texas Southwestern Medical Center in Dallas. Still, Shay muses, the idea of linking more human food to shortened bear hibernation and faster cell aging may be correct. Power Words (more about Power Words)
atmosphere The envelope of gases surrounding Earth or another planet.
carbon The chemical element having the atomic number 6. It is the physical basis of all life on Earth. Carbon exists freely as graphite and diamond. It is an important part of coal, limestone and petroleum, and is capable of self-bonding, chemically, to form an enormous number of chemically, biologically and commercially important molecules.
cell The smallest structural and functional unit of an organism. Typically too small to see with the unaided eye, it consists of a watery fluid surrounded by a membrane or wall. Depending on their size, animals are made of anywhere from thousands to trillions of cells.
chromosome A single threadlike piece of coiled DNA found in a cells nucleus. A chromosome is generally X-shaped in animals and plants. Some segments of DNA in a chromosome are genes. Other segments of DNA in a chromosome are landing pads for proteins. The function of other segments of DNA in chromosomes is still not fully understood by scientists.
diet The foods and liquids ingested by an animal to provide the nutrition it needs to grow and maintain health. (verb) To adopt a specific food-intake plan for the purpose of controlling body weight.
DNA (short for deoxyribonucleic acid) A long, double-stranded and spiral-shaped molecule inside most living cells that carries genetic instructions. It is built on a backbone of phosphorus, oxygen, and carbon atoms. In all living things, from plants and animals to microbes, these instructions tell cells which molecules to make.
ecology A branch of biology that deals with the relations of organisms to one another and to their physical surroundings. A scientist who works in this field is called an ecologist.
hibernation A state of inactivity that some animals enter to save energy at certain times of year. Bears and bats, for example, may hibernate through the winter. During this time, the animal does not move very much, and the use of energy by its body slows down. This eliminates the need to feed for months at a time.
link A connection between two people or things.
mammal A warm-blooded animal distinguished by the possession of hair or fur, the secretion of milk by females for feeding their young, and (typically) the bearing of live young.
molecule An electrically neutral group of atoms that represents the smallest possible amount of a chemical compound. Molecules can be made of single types of atoms or of different types. For example, the oxygen in the air is made of two oxygen atoms (O2), but water is made of two hydrogen atoms and one oxygen atom (H2O).
processed foods Foods purchased from a grocery story that are substantially different from the raw materials that went into them. Examples include most foods that come in cans, bottles, boxes or bags. Examples include breakfast cereals, frozen pizzas, canned tuna, jars of spaghetti sauce and dill pickles.
scavenger A creature that feeds on dead or dying organic matter in its environment. Scavengers include vultures, raccoons, dung beetles and some types of flies.
telomere A natural protective cap on the ends of chromosomes, made by successions of a six-nucleotide sequence of chemicals. This chemical sequence is found only on the ends of chromosomes. Its known as TTAGGG, where each T corresponds to a molecule of thymine, each A is a molecule of adenine and each G is a molecule of guanine. Over time, telomeres shorten as they cell theyre in copies itself. If the telomere length gets too short, the cell stops dividing and dies.
tissue Made of cells, it is any of the distinct types of materials that make up animals, plants or fungi. Cells within a tissue work as a unit to perform a particular function in living organisms. Different organs of the human body, for instance, often are made from many different types of tissues.
U.S. Fish and Wildlife Service A research agency of the U.S. Department of the Interior, it was created in 1871 as the U.S. Commission on Fish and Fisheries. Fourteen years later, it acquired an office of ornithology (the science of birds). In 1905 it was renamed the Bureau of Biological Survey. It now has authority for research on and the conservation of land-based species, of freshwater species and of migratory birds.
Fat bears = bigger rugs, yay!
Makes humans fat and sleep more. Go figure. Humans and bears must not be the same. Or not, both like donuts.
most humans eat “junk “ food.
Especially in those pic-a-nic baskets
Yeah, and they spend more time watching late-night TV.....
Imagine all the Grant Money that will roll for these worthless studies.
Their not worthless, they get lots and lots of government bucks.
Calorie rich, energy dense foods, the bears don’t need to hibernate as long. Gee, there’s a surprise. Normally in the wild bears eat bugs, or fish, carrion etc. Hibernation is an adaptation to very lean living conditions I expect.
When Lewis & Clark rolled through the pacific northwest in 1805 they were eating about 10 pounds of lean Elk daily, and they were still hungry, practically starving. Building up fat reserves against privation is the key to survival.
Mickey Dee french fries taste like cardboard now, unfortunately cute commercials won’t change that. They seem awfully insistent on riding on their past reputation.
The average black bear lives what...4-6 years? Who cares what their cholesterol level is what they die? Very few will ever die of natural causes.
Instead of wasting research dollars, they could have watched Open Season... WooHoo bars.
Check them for diabetes
So how many animals have their hibernations disturbed from eating 'junk food' that wasn't created by humans?
This sounds a bit nonsensical. Why would farmed plants accumulate that isotope of carbon in preference to carbon-12, but not plants in the wild? Any Freepers know?
So cute. :D
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