Periplaneta, the genus to which cockroaches belong to, might be considered vermin by most of us; but as it turns out, they’re actually quite useful little critters. Here’s how:
They eat everything
Okay, this may not sound too great at first, but read along and you’ll see why this is a good thing.
Cockroaches eat absolutely everything under the sun, from potatoes to animal carcases to books. This makes them excellent recyclers.
Just imagine. What would you do with thousands of metric tonnes of dead matter, used books and rotten fruits? You can’t responsibly dispose-off them all, can you? This is where cockroaches come in. They eat through absolutely everything and they get rid of your waste for you.
There are over 55 species of cockroaches in the world, of which 12 reside close to humans. The rest live outdoors. Together, they recycle millions of metric tonnes of waste each year.
They sustain life
Okay, this is going a little far, don’t you think? Nope, because it’s true.
Cockroach faeces is one of the most-powerful natural fertilizers on the planet. Cockroach waste produces huge amounts of nitrogen (courtesy, the decaying matter they feed on), which is then used by plants during their lifecycle.
Without nitrogen, plants won’t be able to survive. Kill enough cockroaches and over time you lose entire forests. And as you know, without forests there won’t be any animals. This includes humans.
So, if you encounter a cockroach, stop and consider this. The cockroach you’re about to stamp, is probably saving your life. Consider giving him a warning and let him off the hook. Poor guy.
Lesson to be learnt
Now, I’ve had my fair share of cockroach kills in my life. And like most people, I never realized how important these creatures were to the ecosystem. But this insight helped me re-think how I view cockroaches. It also made me wonder about other pests like rats. Do they add any value to the Earth too?
As it turns out, they do.
Rats are very intelligent creatures. They’re very adaptable and are quick learners. That’s why they’re the primary subjects of all scientific experiments. But rats and mice do offer value beyond this.
We may hate rats because they’re “icky”, but they function as prized food for animals like cats, snakes, eagles, falcons, owls and weasels, amongst others; most of whom are beloved the world over. Imagine what would happen to them if rats were to go extinct.
Humans may be able to survive the loss of their lab companion. But do you think other animals could survive the loss of prey?
What can we take away from this?
Every animal on the planet fulfills a purpose. Learning about these animals can help us understand what this purpose is. More importantly, this knowledge can prevent our committing harsh actions against them, which may ultimately have a long-standing negative impact on the planet.
But in saying this, its also important to note that animals like cockroaches and rats are considered pests for a reason. They spread germs and disease and they wreak havoc on farm produce. Killing them can prevent these pests from overrunning the planet and keep the Earth safe.
But for this to be executed correctly, it must be done in a controlled manner and a need-only basis.
What do amphibians, reptiles and fish have in common? They are all ectotherms – cold blooded creatures. They are animals which cannot regulate their own body temperatures (like warm blooded animals can) and they rely on the external environment to change their internal temperatures.
For long scientists wondered if sickness like cold, flu and fever were the lot of warm blooded creatures . As it turns out – they aren’t. Cold blooded creatures can fall ill too.
How (?), you may ask. In order to understand this, we need to understand how fevers set in warm blooded creatures.
All warm blooded creatures have a particular body temperature, which for them is considered normal. For example:
Humans – 98.6°F
Dogs – 102.0°F
Elephants – 97.7°F
Horses – 100.4°F
Goats – 103.4°F
If the body temperatures of these animals rises above this limit (as is the case during infections), the body tries to thermoregulate .i.e. bring the temperature back down, to normal. When the body fails to do this and the body temperature continues to rise, fever sets in.
What about cold blooded animals?
Based on this, it’s important to note that for fever to set in, there has to be a biologically-set body temperature. But cold blooded animals don’t have a fixed temperature. Their body temperature falls or rises depending on the temperature of the external environment.
So, how do they fall ill?
Well, cold blooded or warm blooded, all animals are susceptible to illness. Just as with their warm blooded cousins, cold blooded animals too may get infections from parasites or viruses, which can raise or drop their body temperatures abnormally. Just like warm blooded animals, ectotherm animals’ bodies too can handle only a certain level of heat and cold. If the change in temperature during the infection falls beyond this limit, illness similar to fever sets in.
But the biggest mystery here isn’t just about how these animals fall ill, but it also includes what these animals do to get back to health.
Changing behaviours for the sake of wellness
When fish, amphibians or reptiles fall ill, they indulge in what is known as a “behavioural fever“. If the animal is infected by a parasite or virus and experiences signs of ill health, it moves away towards areas which support warmer climates. For example, fish that normally prefer cold waters may swim towards warmer waters when they are ill.
Heat has the ability to deactivate viruses and destroy the proteins which assist in virus duplication. The same goes with parasites – heat can kill them too.
So, a cold blooded creature that falls ill, will instinctively move towards a warmer place, in order to increase its body temperature, which will in turn help in killing or deactivating the pathogen in their bodies.
This instinctive “behaviour“, which ectotherms exhibit when they have “fevers“, is called “behavioural fever“. Scientists speculate this behaviour could stem from the fact that the immune systems of cold blooded animals may actually function better when in warmer climates.
One of the best examples of cold blooded creatures who exhibit behavioural fever are Zebrafish. The moment they fall ill, Zebra fish will change their water-heat preferences and swim to warmer waters. The same goes for Guppies.
When behavioural fever benefits the host
For some time, it was assumed that behavioural fever was helpful only for ectotherms who were in the throes of infection & fever. But as it turns out, in some cases, the move to hotter areas benefits pathogens too.
Schistocephalus solidus, a tapeworm found in the gut of rodents, fish and fish-eating birds, actually thrive on heat. Once the parasite is in the hot climate, it grows stronger and changes the heat preferences of the fish and manipulate other atypical (and often self-destructive) behaviours in the animal.
Then there is the Cyprinid herpesvirus 3, which is a virus that attacks fish in the Carp family. This virus affects the genetic code of the fish it infects and overrides the genes which stimulate behavioural fever. So, the infected fish doesn’t move towards warmer waters (as it is supposed to), instead choosing to stay in colder waters, where the virus can gain in strength.
What happens if a feverish ectotherm cannot move to warmer climates?
Vicious parasites and mind-control viruses aside, the inability to indulge in behavioural fever can have a massive, negative impact on cold blooded animals. This is in fact, very true of pets.
In the wild, cold blooded creatures have a lot of freedom to move to different places, in order to rid themselves of their illness and infection. But pets stuck in aquariums and enclosures don’t have this luxury.
Cold blooded pets like fish, turtles, tortoises, iguanas, lizards and snakes are cooped up inside their temperature-controlled tanks/enclosures for almost their entire lives; where they are subjected to the same temperature day-in-and-day-out.
Now imagine these pets fall ill and have a fever. Biologically they are programmed to leave and move to a place that is warmer, to heal themselves. But because they are stuck in their tanks/enclosures, these animals do not get the opportunity to get their bodies at the right temperature to kill the infection.
When this happens, the fever and the infection only gets worse and in the worst cases, the pet dies. In fact, a large number of fish deaths in aquariums can be attributed to this.
So, what can pet owners do about this?
Fish owners can set aside a separate tank where they can change the temperature of the water as required. Owners of amphibians and reptiles can create heat spots in corners of the enclosure by using detachable heaters and small light sources. This can give the sick pet an opportunity to self-heal.
If however, your pet looks worse, it’s best to take him/her to a vet immediately.
Posssums are marsupials (pouched mammals) that are found in North America. They are the only marsupial species found outside Australia and New Guinea. They belong to the order Didelphimorphia, to which belong 95 species of possums.
Here are 5 fun facts about them:
Possums are renowned for their ability to “play dead”. In reality, possums don’t actually “play” dead. Their paralysis and almost-dead like state is an involuntary physiological reaction where their nerves and muscles literally freeze and stop working for hours due to stress. This in-built defense mechanism has allowed the possum to survive from pre-historic times.
Lyme disease is a tick-bite induced disease that results in terribly itchy and inflamed rashes, joint pain and fatigue. Possums in your backyard is a great defense against Lyme disease. It’s been found that possums prey on over 5000 of the ticks and fleas that spread the bacterium Borrelia burgdorferi, which causes Lyme disease.
Apart from the venom of the Coral Rattlesnake, possums are immune to all other snake venom. That’s why they regularly prey on snakes in the wild. A few years ago researchers created an anti-venom using possum peptides (short chain amino acids linked by peptide bonds), which they injected into mice. They then injected snake venom into the mice only to find the venom absolutely useless.
Rabies virus require very hot temperatures to develop and spread. But possums have very low body temperatures compared to other mammals and this makes them invulnerable to rabies. You can almost never find a possum with rabies.
Primates aren’t the only species to be gifted with opposable thumbs. Possums have opposable thumbs called “halux” on their feet and they use them to climb atop the steepest trees and into the deepest sewers in search of food.
Contrary to popular belief, possums and opposums aren’t the same animal. They also don’t belong to the same species. For one, possums belong to the Didelphimorphia order in North America, while opossums belong to the order Phalangeridae in Australia. Both animals look similar, but behave completely differently. It was because of this similarity in physical features that led scientists to confuse the opposum for a possum.
April 4th is celebrated as World Rat Day. This day was chosen in honour of the date of incorporation of the Ratlist, a mailing list that’s dedicated to the care and upkeep of pet rats.
A rat’s whiskers are its “hearing” devices. The whiskers pick up vibrations from the ground and inform the rat the size of the object/creature coming towards it and the direction it is coming from.
Rats have been observed making a high-pitched laughing noise when they play.
A rat’s teeth never stop growing. They can grow up to 5 inches per year. These teeth are so strong, they can gnaw through lead and aluminum sheeting!
Rats have really good memories and can recognize faces & places. Their superb memory is one of the reasons why they don’t get lost in mazes and drain pipes.
In countries like Cambodia, Angola and Zimbabwe, Giant African rats are trained to detect landmines. In fact, these rats have saved countless lives through their super-rat landmine-detecting abilities.
To qualify as a landmine-detector, the rats have to undergo a gruelling 6-9 months training and must pass an accreditation test. Read all about this interesting processhere. You can also meet some of these heroes at Apopo.
“Anorexia nervosa is a complicated disorder and genes aren’t everything. The genes load the gun but the environment pulls the trigger.”
-Dr. Janet Treasure
When Dr. Janet Treasure, senior lecturer at the London Institute of Psychiatry conducted her research into the origins of Anorexia nervosa in humans, she found herself following a path not many knew about; but which could explain how Anorexia functions in human beings.
This path less travelled by, was the study of a disease that only few knew existed and which hardly any understood – Pig Anorexia.
The day the pigs came calling
It was in 1962 at a farm in Ontario, Canada that the resident pig keeper noticed something amiss with the new litter of piglets. The tiny creatures had been recently weaned from their mother and were being fed by hand by the farm boys.
While things seemed fine at first, the pig keeper noticed the piglets had stopped eating soon after, often starving themselves for days until they were just skin and bones. With this starvation came the vomitting, the weakness and the weight loss.
The hunger, combined with the deteriorating condition of the body, soon grew too much for the tiny piglets to cope with and the entire farrow lost its life.
This was the very first case of ‘pig anorexia’ as it soon came to be called and it is a disease that has affected pigs the world over.
In every living creature, the DNA is the genetic blueprint of the body and it dictates the physiological and psychological make-up of the creature. The RNA is an acid present in the cells, which carries messages from the DNA and stimulates the production of proteins. These proteins are used by the cells to develop and control the functioning of the various organs inside the animal’s body.
Multiple RNA strands work within the cells of an animal’s body throughout its life. Ultimately, the RNA are responsible for the health of the proteins, the cells and the animal itself.
Now imagine if the HEV were to infect the RNA of the piglets. Each and every time an infected RNA would stimulate the production of proteins in the body, the proteins and by extension the cells, would be infected too.
Slowly over time, the HEV starts infecting the piglets from the cellular level by making their cells and organs diseased.
How does HEV spread?
HEV is just like any other virus and it spreads from contact with body liquids. These liquid spread between snout-to-snout contact and can also spread to pigs through indirect contact with boots, jackets, farm equipment etc. if pig saliva or mucus is splattered on them.
It’s been observed that most porcine populations are exposed to these viruses everyday. But only 1% – 4% of the population ever experience an active attack. Piglets are the most vulnerable to the virus, given their lack of immunity and strength.
Infected piglets will often have microscopic lesions inside their snout, on their tonsils and on the walls of their stomach. When the virus spreads, it moves to the lungs, small intestine and finally the brain through the sensory nerves. It is when the virus reaches the brain that piglets exhibit full-fledged anorexia-like symptoms.
The HEV has been observed re-writing the signals sent to the brain, changing the behaviour of the piglets. The affected piglets display low hunger levels at first and soon start skipping meals. During later stages of the disease, they may vomit extensively and may start dehydrating as a result. The muscles start to wear-out and soon, the piglet is just skin and bones. Death is an inevitable result of the disease.
The HEV-induced infection is a porcine-only infection and does not spread to humans.
Why is it called pig anorexia?
Anorexia nervosa is an eating disorder in humans, where the sufferer stops eating or refuses to eat and starts exhibiting a variety of symptoms including:
Sudden loss of weight
Constant vomiting and diarrhoea
Extreme weakness and lethargy
Low tolerance to heat or cold
Pigs infected by the HEV display symptoms so close to Anorexia nervosa, that the disease has been named Pig Anorexia.
It can get extremely challenging to diagnose the presence of HEV in pigs. For one, symptoms resemble other diseases like Encephalitis, Vomiting & Wasting Disease or the Classical Swine Fever (or Hog Cholera). The only way now to identify if a porcine herd is a victim of the HEV, is to understand their origins and their environment.
Of birth and breeding
Pig pens are extremely fertile incubation areas for the Hemagglutinating Encephalomyelitis Virus (HEV). Once the virus takes root, it cannot be eliminated. The reason for this is the lack of a cure. To this day, there is no clinical cure available to help affected piglets.
But, there is something pig breeders can do to reduce herd vulnerability.
Piglets get high immunity from the colostral antibodies found in the mother’s milk. Putting piglets onto the teat at the earliest can reduce chances of an infection by half. Second, keeping the pen clean and free of fecal matter can reduce chances of infection further.
But this still won’t be enough. It’s been observed that susceptibility to the HEV is also affected by genetics. Pigs birthed naturally, without human intervention have the highest chance of survival as they have the most natural genetic structure which is designed to combat fatal illnesses.
However, with humans preferring leaner bacon cuts over thicker ones, pig farmers are deliberately isolating and promoting those genes which give rise to thinner piglets. This type of genetic manipulation, makes the piglets weaker and more susceptible to infections, including the HEV.
Dr. Janet Treasure said, anorexia is as much about genes as it is about the environment. When combined with the weak genes, the poor rearing environment and pathetic post-birth care practices can double the chances of piglets developing anorexia-like symptoms post-weaning.
Pig anorexia – shattering the body and the mind
Physically, the impact of HEV-induced pig anorexia is nightmarish. Thousands of pigs die each year because of the lack of veterinary care. Exposure to infected piglets often puts other healthy animals too at risk and increases the headcount.
A 2013 research∗by Reimert, Bolhuis, Kemp, & Rodenburg showed how untrained pigs when introduced into a new pen of trained pigs, adopted the behaviours and mannerisms of their trained counterparts, after sustained exposure to them. These behaviours and mannerisms included everything from the way the tails were held to the vocalizations made to the choice of food the pigs were making. This could be an attempt at social acceptance by the pigs or a mimicry of a positive stimulus-response behaviour.
Now let’s apply the same logic here. Imagine if new pigs are introduced to an infected herd which displays signs of starvation, depression and social isolation. The new pigs too are more likely to mimic this refusal of food and they may socially isolate themselves, following the example of the herd.
This psychological impact that the HEV has on healthy pigs, can lead to true pig anorexia, with pigs refusing to eat out of fear, anxiety or depression.
The human connect
The idea that pig anorexia could bring about a breakthrough in the study of anorexia in humans was unthought of. But during her study, Dr. Treasure realized how similar pigs were to humans in terms of psychology and social behaviour.
Her study into pig anorexia helped her understand a key component about Anorexia nervosa – while genes do play a vital role in indicating susceptibility to the disorder, it is the environmental factors that finally trigger the condition. Essentially, people may be pre-disposed to anorexia through genetics, but this pre-disposition is unlikely to have a major negative impact so long as the person’s upbringing is filled with love and support.
Just like fecal matter in pig pens, constant negative feedback from family can make people more likely to suffer from anorexia. Remove this environmental contamination and you reduce the subject’s vulnerability to the disorder. This insight is now helping medical professionals find lasting treatments for anorexia in humans.