Tag Archives: Pet

Plastic-eating bacteria turns waste into vanilla flavoring

Example of PET waste. Credit: pixabay.

The invention of plastic has been one of the most important cornerstones to raising our standard of living in the past century. However, the same qualities that make plastic so desirable to consumers — in particular, its very low cost and high durability — also make it a bane to the environment. This is why scientists across the world are busy researching sustainable solutions to our growing plastic litter problem, either at the source (i.e. finding biodegradable alternatives) or during waste treatment.

One such effort focused on the latter. Researchers at the University of Edinburgh in Scotland devised an experimental method that converts treated polyethylene terephthalate (PET) — the lightweight plastic used to package everything from beverages to food — into vanillin, the primary ingredient extracted from vanilla beans that creates the characteristic taste and smell of vanilla.

To do so, the researchers turned to the common E. coli bacteria, which is found virtually everywhere, including your lower intestines. They engineered a strain to consume terephthalic acid, a molecule derived from PET, and transform the substance in vanillin, through a series of chemical reactions.

During one experiment, the E. coli turned a used plastic bottle into vanillin which should be fit for human consumption. Subsequent research will determine whether or not this plastic-derived vanilla compound is indeed safe to eat.

“This is the first example of using a biological system to upcycle plastic waste into a valuable industrial chemical and this has very exciting implications for the circular economy. “The results from our research have major implications for the field of plastic sustainability and demonstrate the power of synthetic biology to address real-world challenges,” said study first author Joanna Sadler of the School of Biological Sciences at the University of Edinburgh.

This research is exciting because it could solve two problems in one go. Every year, people across the globe produce about 50 million tonnes of PET waste with important economic and environmental consequences. Whilst PET is one of the most easily recyclable plastics, most still ends up in landfills or, worse, the ocean.

Meanwhile, people love vanilla! In 2018, global demand for vanillin was in excess of 37,000 tonnes. The compound is not only used in food but also in other industries from cosmetics to herbicides.

Thus, using bacteria to convert a harmful waste into a valuable product is a fantastic one-two punch.

“Our work challenges the perception of plastic being a problematic waste and instead demonstrates its use as a new carbon resource from which high-value products can be obtained,” said Stephen Wallace, co-author of the new study and a researcher at the School of Biological Sciences at the University of Edinburgh.

In the future, the researchers in Scotland plan on performing further strain engineering, process optimization, and extend the pathway to other metabolites so they might turn plastic into useful compounds other than vanillin.

The findings appeared in the journal Green Chemistry.

Newly-discovered enzyme cocktail paves the way towards infinitely recyclable plastic

The researchers who made the improved version of the plastic-eating PETase enzyme have now developed a new ‘cocktail’ that can break down plastic much faster.

Image credits Džoko Stach.

Half of the cocktail is made up of the previous enzyme, PETase. The other ingredient, MHETase, is an enzyme found in the same strain of bacteria from which PETase was isolated. Together, they can break down plastic six times faster than alone, the team explains.

The findings can help pave the way towards improved plastic recycling methods, the team explains, which would slash plastic pollution as well as the emissions from plastic production.


“It took a great deal of work on both sides of the Atlantic, but it was worth the effort—we were delighted to see that our new chimeric enzyme is up to three times faster than the naturally evolved separate enzymes, opening new avenues for further improvements.”

Arguably the best place to find plastic-consuming compounds is in colonies of bacteria living on a diet of plastic bottles. But it turns out that it’s also the best place to find such a compound again.

The team isolated MHETase from the same strain of bacteria that produced PETase. Put together, the two are much more efficient at clearing out plastics than apart.

PETase decomposes polyethylene terephthalate (PET), a very common plastic used among other things for bottles, into its chemical components. This opens up the way — at least in theory — to infinitely-recyclable plastics.

Plastic is so useful because, on a chemical level, it is incredibly stable. The other side of the coin is that this makes it virtually indestructible by biological activity and other natural processes in any meaningful timescale (it takes several hundreds of years for it to break down in the environment). It also makes plastic hard to reuse over multiple cycles, as the process of breaking and reforming its chemical bonds has a noticeable effect on its physical properties.

After PETase was first isolated, the team worked to engineer it in the lab to make it more effective. By the end, they made it around 20% faster in breaking down PET.

MHETase, they explain, works as the teammate of PETase in the wild. Put together, they’re twice as fast in breaking down PET. After tweaking it in the lab, the team improved the effectiveness of this cocktail threefold — meaning that it breaks down plastic six times faster than PETase alone. What the team did in the lab is to essentially link the two molecules together chemically, instead of having them as separate solutions. Because of this link, PETase always has a MHETase molecule on hand to boost its speed.

“Our first experiments showed that they did indeed work better together, so we decided to try to physically link them, like two Pac-men joined by a piece of string,” says Professor John McGeehan, Director of the Centre for Enzyme Innovation (CEI) at the University of Portsmouth.

The resulting MHETase-PETase molecule breaks down plastic to its constituent parts, allowing for it to be recycled endlessly. The team hopes that the findings can help decrease reliance on crude oil or natural gas for raw materials and that they will help lower the emissions and pollution caused by plastic production.

The work, however, isn’t done. The authors used the Diamond Light Source in Oxfordshire, the UK’s largest synchrotron, to study the atomic structure of MHETase-PETase. Armed with its 3D structure, they are now working on designing a synthetic molecule that would perform the same task but faster and more efficiently. If successful, we might be able to engineer bacteria, or design completely synthetic ones, to produce plastic-destroying enzymes to clean out landfills and the ocean.

The paper “Characterization and engineering of a two-enzyme system for plastics depolymerization,” has been published in the journal PNAS.

Dogs really help people stay fit, new study shows

As if dogs weren’t precious enough, they also help with our fitness — new research shows that dog owners are 400% more likely to meet recommended physical activity guidelines.

Dog owners were found to walk their dogs for a median 7.0 times per week (range 0–32), covering a median total of 220.0mins per week.

The fact that dog owners tend to do more exercise shouldn’t really surprise anyone — whether you like it or not, you have to go walk the dog. However, previous research mostly focused on a single household member, and it’s not exactly clear whether time spent dog walking replaces other physical activity. In the latest study, researchers analyzed just what kind of a difference having a dog really makes — fitness-wise.

Carri Westgarth and colleagues from the University of Liverpool assessed the self-reported physical activity of 385 households in the, UK (191 dog owning adults, 455 non-dog owning adults and 46 children). Researchers also tracked 28 adults with an accelerometer, to have a confirmation for the total physical activity.

They found that dog owners walk more frequently and for longer periods than non-dog owners — and this activity doesn’t replace other physical activities. In other words, it’s simply extra physical activity. Researchers were able to confirm the health-enhancing potential of dog ownership.

“Evidence suggests dog ownership is associated with lower risk of death, and a lower risk of cardiovascular conditions at least in single-person households, where the participant may be more highly obligated to dog walk,” the study reads.

For many people, this could be the difference between healthy and unhealthy levels of exercise. Researchers recommend doing at least 150 minutes of moderate-to-vigorous physical activity per week. However, less than 50% of adults in the USA actually achieve this. England fares a bit better, but still, only 66% of men and 58% of women achieve this bare minimum goal. This study found that dog owners were four times more likely to achieve this goal. Furthermore, the benefits extend to all household members involved in dog-walking.

The results are so positive that researchers actually call for policy to support more dog ownership, considering the health benefits associated with it.

“Dog ownership is associated with more recreational walking and considerably greater odds of meeting physical activity guidelines. Policies regarding public spaces and housing should support dog ownership due to physical activity benefts,” the team writes.

So if you’re struggling to lose weight or be physically active, there’s a woofing solution to that.

The study “Dog owners are more likely to meet physical activity guidelines than people without a dog: An investigation of the association between dog ownership and physical activity levels in a UK community” has been published in Scientific Reports.


Cow pats.

Why do pets like pats?

Why do we, too, like pats for that matter?


Think it’ll turn into a handsome prince?
Image credits Juda / Pixabay.

If you happen to have your own little, warm ball of fur back home, you know how much they love to be pet. But why do they like it, exactly? And do we humans like it, too? Let’s find out.


Dogs love belly rubs. Cats break into a purr when you scratch that one special place between their ears. Hugs give us comfort and pleasure. If you hit your hand on something, a quick rub will reduce the pain.

All of these are fundamented on the sense of touch and show what a massive role it plays on our emotional state. While not all touches are pleasurable, all mammals seem to agree that a longer, slighter stroking motion feels good.

This particular type of motion stimulates a set of neurons known as MRGPRB4+, reported this study published in Nature Neuroscience in 2007. The authors worked with genetically-engineered mice, whose MRGPRB4+ neurons were modified to light up when activated (optogenetics). Pet-like stroking patterns of touch — and only this pattern of touch — at temperatures around that of human skin activated the neurons, the team found, inducing a pleasant sensation in the animal.

These neurons are connected to hair follicles in the skin and are relatively widely-spaced. Their layout is what makes them only respond to long stroking motions, and not more localized ones like pinching or poking.

Orange cat pet.

Image credits Linnaea Mallette.

We also have these neurons built into the follicles of hair-covered portions of our skin. This suggests that MRGPRB4+ neurons respond to touch on the skin itself, not to motions transmitted through strands of hair. This is also supported by the fact that an individual can experience a pleasant sensation from petting, hugging, or stroking even after experiencing hair loss or shaving; if the MRGPRB4+ neurons were tied to hair strands, instead of follicles, this wouldn’t have been the case.

“The researchers suspect similar sensory neurons with comparable properties exist in humans and most furry mammals,” explained David Anderson, one of the study’s co-authors.

“Since the sensation is connected to hair follicles, animals with many of them, such as cats and dogs, likely feel waves of pleasure when being petted. The neurons that detect stroking are probably wired into higher brain circuits that produce a reward or pleasure.”

To validate these findings, the team further modified some mice so that the same neurons could be activated biochemically, via a drug injection. When given the choice between two chambers, a control one where nothing happened and one where the drug-induced touch sensation occurred, the mice opted for the latter. This implied that the animals actually found the sensations caused by MRGPRB4+ neuron activation to be pleasurable. The mice also showed fewer signs of stress after receiving their chemical pat.

So, to recap, furry, hairy animals (i.e. mammals) enjoy the sensation of being pet. It is mediated by neurons connected to hair follicles in the skin and only caused by deliberate, slow, gentle, and relatively long strokes on the skin or fur. But we’re still missing a why — why did mammals evolve to experience pleasure from these patterns of touch?

Making buddies


“So how are you how’s the kids?”
Image credits Anthony / Pixabay.

For mammals, especially social ones, touch is a great way to make friends and strengthen bonds. Our wild cousins groom each other to remove harmful parasites from their fur since they can’t do it by themselves. But past research has shown that they engage in this behavior far more than than necessary from a purely hygienic standpoint. So, while grooming might have a very practical, even critical purpose, primates also seem to simply get a kick out of it and do it for fun or to socialize. It’s how they hang out.

Us humans aren’t typically big on public displays of grooming, but we also employ touch socially. Hugs, handshakes, a tap on the shoulder, they’re small gestures that can go a long way in strengthening familial or social bonds.

The mammal enjoyment of pats probably started out as a practical ritual — for example, as grooming — and our physiology later evolved to encourage the activity with positive sensations. Such behavior likely represented an evolutionary advantage as it promotes health, hygiene, bonding, and trust among the group, thereby increasing the survival chances of all its members. Alternatively, it is possible that this enjoyment of pats helps baby mammals keep warm by balling up together with their parents and siblings, thus conferring a selective advantage at a young age.

Regardless of why it happens, the end result is extremely effective at promoting bonding, social interaction, and good moods. Activation of the MRGPRB4+ neurons releases endorphins and oxytocin into the brain (these help with pain relief, relaxation, and bonding) and may lead to temporarily-reduced cortisol (a stress hormone) levels. This chemical cocktail puts us, or our pets, at ease, nips aggression in the bud, and induces a state of pleasure.

In your brain

One paper published in NeuroImage in 2016 looked into the patterns of “brain activation during 40min of pleasant touch” — which sounds quite enjoyable. The authors worked with 25 participants who “were stroked for 40min with a soft brush while they were scanned with functional Magnetic Resonance Imaging [fMRI], and rated the perceived pleasantness of the brush stroking.”

What they found was that stroking heavily activates neurons in the somatosensory cortex initially, although this dwindles in intensity over time — likely due to stimulus habituation. Stimulus habituation is the thing that makes you less sensitive to a particular smell after being exposed to it for a while, why you eventually stop feeling the chair under you or the smartphone in your right pocket.

At the same time, activity levels in the orbitofrontal gyrus (OFC, also known as the orbitofrontal cortex) and the putamen increase, stabilizing at about 20-minute mark. Certain structures of the insular cortex (the posterior insula) also see greater activity during this time. The team believes this increase in cerebral activity comes down to the subjective pleasure each participant was feeling — pleasure is how your brain rewards you for doing something.

The workings of the orbitofrontal cortex have been linked to depression in humans. In particular, reports one study published in Brain in 2016, subjects with depression showed weaker neural connections between the medial (middle) OFC and the hippocampus, which is associated with memory. They also showed stronger neural connections between the lateral OFC and other areas of the brain. The study worked with 421 patients with major depressive disorder and 488 control subjects.

The study’s authors explain that the medial OFC activates when processing or ‘administering’ rewards in the form of pleasure. It’s not yet understood exactly what those weaker connections mean, but it does suggest that people with depression may find it more difficult to access and recall happy or positive memories. At the same time, the lateral OFC — which enjoys stronger connections with other brain areas — is involved in processing or administering the non-rewards: science-speak for ‘punishments’.

To tie it all into a neat little bow, one paper published in Current Biology last year reported that the “lateral OFC is a promising new stimulation target for treatment of mood disorders” such as depression. The team worked with 25 subjects, using electrodes to stimulate various areas of their brains while monitoring and recording their (self-reported) mood via a daily questionnaire.

Patting, stroking, massages — they activate the neurons in the OFC, which is exactly what the team achieved using their direct stimulation techniques. A literal gentle touch, then, may be just what you need when you’re struggling with depression.

And hey, if nobody’s around to pet you, grab a brush, clear out 20 minutes of your schedule, and go hack your OFC.

PET plastic bottle.

New upcycling process for PET could finally nudge us into cleaning the seas

Researchers from the U.S. have developed a new recycling method that not only makes the polyester PET longer lived, but stronger and more valuable.

PET plastic bottle.

Image via Pixabay.

A lot of the plastic objects you use every day, from beverage bottles to clothes and carpets are made from polyethylene terephthalate (PET), a type of polyester. Like most plastics, PET is recyclable — but it also degrades during this process, the team writes. PET thus loses value over time. Another problem is that we just tend to churn out a lot of PET — roughly 26 million tons per year — and later toss is straight into the landfill and oceans. There, the roughly 80% of PET we don’t recycle wallows for a few hundred years before biodegrading completely.

One team of researchers plans to fix this by developing a recycling process that actually makes the PET better than it was initially.


“Standard PET recycling today is essentially ‘downcycling,'” says senior author Gregg Beckham, a Senior Research Fellow at NREL.

“The process we came up with is a way to ‘upcycle’ PET into long-lifetime, high-value composite materials like those that would be used in car parts, wind turbine blades, surfboards, or snowboards.”

Researchers at the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL) are behind the new recycling process. They combined reclaimed PET with products derived from renewable material, such as waste plant biomass. Two types of fiber-reinforced plastics (FRPs) were created this way, both of which are two to three times more valuable than the original PET, the team reports.

They also predict that these composite products would require 57% less energy to manufacture than PET reclaimed through the current recycling process. It would also emit 40% fewer greenhouse gases than standard petroleum-based FRPs, which the team calls ‘significant’.

“The idea is to develop technologies that would incentivize the economics of PET reclamation,” says Beckham. “That’s the real hope—to develop ‘second-life’ upcycling technologies that make single-use waste plastic valuable to reclaim. This, in turn, could help keep waste plastic out of the world’s oceans and out of landfills.”

The new materials, however, aren’t ready to leave the lab. The team plans to analyze their properties further and to determine how well the process would scale to a manufacturing setting. They also hope to develop composites that can themselves be recycled; the current ones can last years and even decades but are not necessarily recyclable afterward. They also want to develop similar technologies for other types of materials.

The findings could help protect oceans from PET waste by offering an attractive method of recycling the material.

“The scale of PET production dwarfs that of composites manufacturing, so we need many more upcycling solutions to truly make a global impact on plastics reclamation through technologies like the one proposed in the current study,” says first author Nicholas Rorrer, an engineer at NREL who also participated in the study.

The paper “Combining reclaimed PET with bio-based monomers enables plastics upcycling” has been published in the journal Joule.

Cat market fish.

Veterinary community releases tips and tricks on how to properly feed your cat

The American Association of Feline Practitioners (AAFP) released a Consensus Statement yesterday, advising cat owners on how to better feed their pets.

Cat market fish.

Image via Pixabay.

Aren’t cats awesome? They pad into our lives on their little feet one day, and proceed to make everything better. We want to take good care of them in return, but the way we feed our cats may cause them all sorts of problems, the AAFP explains. Luckily for us, the association has also released a “how to feed” guide to help keep our pets in good health.

Pawsitively educational

“Currently, most pet cats are fed in one location ad libitum, or receive one or two large and usually quite palatable meals daily. In addition, many indoor cats have little environmental stimulation, and eating can become an activity in and of itself,” says the Consensus Statement’s chair, Tammy Sadek.

“This current type of feeding process does not address the behavioral needs of cats.”

The manner in which most people feed their cats is a poor match for the behaviors these animals have evolved with, the document explains. Cats are naturally tailored to hunt and forage for their food. They tend to eat small but frequent meals, and generally do so in a solitary fashion. It may be quite time and effort intensive to create these feeding conditions for your cat, but it does pay off — allowing cats to exhibit these feeding behaviors regularly can help alleviate or prevent stress (and obesity) related issues such as cystitis, inactivity, and overeating.

A more natural feeding program can also help anxious cats mellow out. This will have particularly beneficial effects for anxious cats that share a household with other felines — and so may not access the food frequently enough, causing weight loss.

“Appropriate feeding programs need to be customized for each household,” Sadek adds, “and should incorporate the needs of all cats for play, predation, and a location to eat and drink where they feel safe.”

The Consensus Statement is accompanied by a small brochure that offers some helpful tips on how to provide a feeding environment that keeps cats happy and well (but not over-) fed.

[panel style=”panel-info” title=”Here are some I found particularly helpful or interesting” footer=””]

  • Using puzzle feeders and hiding kibbles around the home gives your cat some exercise, keeps it entertained and stimulated (both mentally and physically), and improves weight management without too much hassle on your part. Simple, easily manipulated puzzle feeders should be introduced first.
  • Placing bits of food in different or new locations, including elevated areas when the cat’s physical status allows, can help offer cats forage opportunities and engage their senses in searching for food.
  • A cat’s daily food allowance should be split into multiple small meals over a 24 h period.
  • The caloric needs of your cat will vary over time — talk to your vet, monitor your pet’s condition, and adjust food portions accordingly. Food can be measured when filling feeding stations and again 24 h later to determine how much your cat has eaten.
  • Treats shouldn’t exceed 10% of the pet’s daily caloric intake, in order to avoid dietary imbalances. Small treats work best since they’re easily consumed, your cat enjoys them, and they’re low on calories.
  • Have separate watering stations throughout your home.
  • Cats generally like to eat alone. They tend to view the feeding area as their safe space. In multi-cat households, separate feeding areas (it’s important that they are visually separated, i.e. out of sight of each other) can help reduce anxiety, stress, and their associated health complications.
  • Feeding stations should not be close to litter boxes.


The Consensus Statement also highlights the importance of feeding programs, and the criteria they should take into consideration. If you want to set up a feeding program for your pet, the AAFP recommends you set a clear goal — ‘my cat needs to lose weight’, ‘I want to improve its nutrition’, etc. — and then work with a veterinary professional to design the program.

All in all, I’m definitely going to implement a few of these tips when I get back home today.

The paper “Feline Feeding Programs: Addressing behavioral needs to improve feline health and wellbeing” has been published in the Journal of Feline Medicine and Surgery.

Man with dog.

That ridiculous voice we use to talk to dogs? They actually love it

A high-pitched voice and exaggerated emotion when interacting with a dog will get you a long way, science says.

Man with dog.

Image credits Besno Pile.

University of York researchers say that the way we speak to our dog-friends is a key relationship building element between pet and owner. The effect is similar to how ‘baby-talk’ helps adults bond with babies.


Previous research suggests that talking to a puppy in a high-pitched voice, with the customary exaggerated amount of emotion, helps improve engagement. New research from the University of York tested whether this effect holds true for adult dogs as well. Their results suggest that using this “dog-speak” can also help improve attention, and helps strengthen the bond between owner and pet.

“A special speech register, known as infant-directed speech, is thought to aid language acquisition and improve the way a human baby bonds with an adult,” said first author Dr. Katie Slocombe from the University of York’s Department of Psychology. “This form of speech is known to share some similarities with the way in which humans talk to their pet dogs, known as dog-directed speech.”

This high-pitched, rhythmic speech is widely used in human-dog interactions in western cultures, but we don’t actually know if it’s any good for the dog. So, the team set out to find whether the type and content of the conversation help promote social bonding between pets and their human owners.

Unlike previous research efforts on this subject, the team placed real human participants in the same room as the dogs — up to now, such studies involved broadcasting speech over a loudspeaker, without any human present. This setting created a much more naturalistic environment for the dogs, and helped the team better control the variables involved — i.e. if the dog not only paid more attention, but would also want to interact more with a person that speaks to them in such a way.

The tests were performed with adult dogs. Each animal first listened to one person who used dog-directed speech (the high-pitched voice) using phrases such as ‘you’re a good dog’ or ‘want to go for a walk?’, then to another person using adult-directed speech with no specific, dog-related content — phrases such as ‘I went to the cinema last night’, for example. The attentiveness of each dog during these ‘talks’ was measured. Following the speaking phase, each dog was allowed to chose one of the two people to physically interact with.

Dogs were much more likely to want to interact and spend time with those who used dog-directed speech that contained dog-related content, compared to the counterparts. But this result by itself doesn’t do much to clear the waters — so the team also performed something of a control trial, meant to give them insight into what elements of speech appealed to the dogs: was it the high-pitched, emotional tone, or the words themselves? During this phase, the speakers were asked to mix dog-directed speech with non-dog-related words, and adult-directed speech with dog-related words.

“When we mixed-up the two types of speech and content, the dogs showed no preference for one speaker over the other,” says Alex Benjamin, PhD student at the department of psychology, paper co-author. “This suggests that adult dogs need to hear dog-relevant words spoken in a high-pitched emotional voice in order to find it relevant.”

“We hope this research will be useful for pet owners interacting with their dogs, and also for veterinary professionals and rescue workers.”

The paper “Alex Benjamin, Katie Slocombe. ‘Who’s a good boy?!’ Dogs prefer naturalistic dog-directed speech” has been published in the journal Animal Cognition.

Russian geneticist breeds the first domesticated foxes and I want one

A Russian geneticist has done something that took our ancestors thousands of years in just five decades. By selectively breeding hundreds of Vulpes vulpes foxes over multiple generations, Dmitry K. Belyaev has created a never-before-seen pet: the domesticated fox.

Image credits Neil McIntosh / Flickr.

On an unassuming farm in Novosibirsk, a new breed of pets is poised to take the world’s hearts by storm. In his quest of recreating the process by which ancient humans turned wild dogs from predators to “man’s best friend’ to learn about domestication, Russian geneticist Dmitry K. Belyaev has created the world’s first docile foxes.

In essence, what he did was husbandry or artificial selection. By basing future generations on individuals who exhibited one desired trait the strongest, he gradually added to the tameness of the animal — this was the same process our ancestors used to increase their crops’ and livestock’s yield and hardiness. The process was pretty straightforward but time-consuming. Belyaev visited fur farms around Russia in the late 1950’s and selected the friendliest foxes he could find. He bred successive generations starting from this stock, selecting the tamest individuals each time.

In the early 2000s, almost all of the foxes on Belyaev’s farm show surprising changes in behavior, reported Lucy Jones for the BBC.

Cuddly, friendly little vixens

Foxes are considered especially hard to tame, but these ones on the farm seem to enjoy their time with people. They acted more like dogs than what we’d expect from a fox — things such as wagging their tails or perking up in the presence of a human. The foxes didn’t show any of the aggressive or skittish nature we expect in wild animals. On the contrary, they would seek out people to pet them and even lick their handler’s face — and you can’t really get more “dog” than that.

Belyaev said this all happens without any sort of training on his part. The only thing he did was to select for the foxes that interacted with humans the best.

“They’re genetically designed to crave human contact,” said Ceiridwen Terrill, a professor of Science Writing and Environmental Journalism at Concordia University in Portland who visited the farm and got to pet the foxes, for NPR.

“So that fox loved having its belly scratched.”

The foxes also started looking tamer over time: their ears got floppier, they developed shorter legs, tails, snouts, and their skulls widened. Their breeding patterns have also changed, and the foxes now mated out of season and had on average one more offspring per litter. In a 2009 paper, Lyudmila Trut of the Institute of Cytology and Genetics at the Russian Academy of Sciences, who now oversees the farm, says this is likely caused by neurological and endocrinological changes promoted through selective breeding.

The paper found that compared to wild foxes, Belyaev’s pets show the difference in brain chemistry. Their adrenal glands are less active but they have higher levels of serotonin, which helps mediate aggressive behavior, Trut writes. The droopy ears could be explained by their slower adrenal system, BBC writes, and the selected hormonal differences could also inadvertently promote physical differences. Dogs likely went through much the same process over the course of hundreds of generations as they gradually adapted to living with us.

The experiment confirms our theories regarding domestication. Not only the fact that we can bend a species evolutionary course in our favor, but also that the process affects more than their behavior. Domestication alters a species looks, inner workings, and the cycles they live their lives by.


Why it’s illegal to own one guinea pig in Switzerland

At first, it sounds like one of the silliest laws ever: in Switzerland, you’re not allowed to own just one guinea pig or parrot. The reason for this is that they’re social species, and they are considered victims of abuse if they aren’t able to regularly interact with others of their species.

Photo by Mikerussell.

If you’re an animal person, you’ll love Switzerland. In recent years, they’ve passed quite a few pet-friendly laws which I hope will be implemented in more places throughout the world. For starters, dog owners must take a course that teaches them how to take care of their dogs, care for their needs and deal with several behavioral situations. Anglers (fishermen) are required to take a course on humane fishing. But perhaps the most heartwarming Swiss law is about guinea pigs: you’re not allowed to have just one! They need social interaction to be happy, so owning a single guinea pig is considered harmful to its well-being and forbidden by law.
They need social interaction to feel good, so owning a single guinea pig is considered harmful to its well-being and forbidden by law.

Animal matchmaking

Guinea pigs are quite curious and inquisitive in nature, but they are timid explorers. They get very attached to their owners and partners. If something does happen to their partner, then owners need to find another one — and that’s not easy (for the humans as well as the guinea pigs). This is why Swiss animal lover Priska Küng runs a kind of matchmaking agency — for lonely guinea pigs.

“Because they hardly ever die at the same time, even if they are exactly the same age, people who don’t want a new guinea pig and lose one of their two animals need an interim solution,” she says.

Her service is in high demand, but it’s also challenging: even though they don’t want to be lonely, guinea pigs can be quite picky about who they live with.

“A young animal can annoy a four or five-year-old guinea pig by being too temperamental and active,” says Küng. But sometimes the opposite is true: Küng has also known guinea pig grandpas to feel rejuvenated by the addition of a younger companion.

What do you think about this approach? Sweden has similar legislation in place and several other countries have sensible laws protecting social animals. Is this something you’d like to see implemented everywhere, or does it feel like overkill?