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The problem of wild animals as pets

Although the first animals we think of as life partners are dogs or cats, the truth is that unfortunately many people decide to have a wild or exotic animal at home. Vietnamese pot-bellied pigs, sugar gliders, fennec foxes, meerkats, raccoons, monkeys… Is it possible to have a wild animal in good condition at home? What are the issues we can find? What wild mammals do people have as pets? We invite you to continue reading to find out.

WHAT IS THE DIFFERENCE BETWEEN A DOMESTIC ANIMAL AND A WILD ONE?

A domestic animal is an animal that has lived with humans for thousands of years. During the history of our species we have artificially selected these animals to obtain benefits, such as food, companionship or protection, like dogs, which have even co-evolved with us. Most domestic animals could not survive in the wild, as they would not know how to find food or would be easy prey for predators. Those who survive when abandoned, like some dogs or cats, cause serious problems to wildlife or even people.

 lobo perro dog wolf perro lobo
Some domestic animals, such as certain dog breeds (right), resemble their wild counterparts (wolf, left), which gives rise to the false idea that wild animals can be domesticated. Photo: unknown

And a wild animal? Many people confuse wild animal with ferocious or dangerous animal. A wild animal is an animal that has not been domesticated, that is, its species has not been in contact with people (at least not for thousands of years as the domestic ones). The fact that some wild animals are not dangerous (or not at all) for us, that they appear in series and movies, some celebrities own them and the desire to have a “special” animal at home, continues favoring the purchase-sale of these animals as pets.

monkey mono capuchino marcel ross friends
The character of Ross in the world-famous series ‘Friends’ had a capuchin monkey, which has to be donated when it reaches sexual maturity for aggressive behavior. Source

WHAT PROBLEMS DOES IMPLY TO HAVE A WILD ANIMAL AT HOME?

PROBLEMS FOR PEOPLE

The main reason why wild or exotic animals cause problems for humans is the lack of knowledge of the species: some have very specific diets that are practically impossible to reproduce in captivity. Others may live longer than the owner, be very noisy, occupy a lot of space, have nocturnal habits, transmit diseases or be poisonous. This results in maintenance difficulties and changes in  the behavior of the animal, until it becomes dangerous for its owner. The consequence is usually the abandonment of the animal, which will cause death, cause problems in nature or very high maintenance costs if they end up in a wildlife rescue center (according to Fundació Mona, keeping a chimpanzee costs 7,000 euros a year. Their life expectancy is 60 years: 420,000 euros in total for a single animal).

Raccoons undergo behavioral changes and may attack their owners. Source

Many species released in the wild end up being invasive, endangering the native ecosystems. If you want to know the difference between introduced and invasive species, read this post. To know the threats they pose to ecosystems, visit this post.

Do not forget that the purchase, sale and possession of many wild animals is totally illegal.

PROBLEMS FOR ANIMALS

Animals must live in an environment where their needs, both physical and mental, can be met. Although we put all our good intentions, give love and spend money keeping a wild animal, we  will never be able to reproduce their natural conditions. Lack of space, contact with other animals of their species, time searching for food, temperature conditions, humidity, light… the animal can not develop its normal behavior even if it is in the most optimal conditions of captivity.

The consequences that will suffer an animal that has not met their needs implies health problems (diseases, growth deficit…) and behavior (stereotypic-compulsive movements, self-injury, anxiety, aggression…).

A fennec fox, a carnivorous animal of the desert, in an evident state of illness. According to social networks, because he was being fed a vegan diet. According to its owner, Sonia Sae, because it is allergic to pollen despite following a vegan diet. Be that as it may, it is clear that the pollen amounts in Sahara have nothing to do with those of Europe. Source

Finally, the most serious consequence when we acquire a wild animal is that we are favoring the trafficking of animals, the death of thousands of them during transport to our house and even their extinction. Animal trafficking is the second cause of biodiversity loss on our planet, behind the destruction of habitats.

Slow loris are nocturnal and poisonous animals that are marketed as pets and, like mostof them, are transported under terrible conditions. Learn more about the calvary of slow lories visiting blognasua. Photo: Naturama

EXAMPLES OF WILD MAMMALS AS PETS

PRIMATES

Marmosets, slow loris, lar gibbons, chimpanzees, Barbary macaques… The list of primates that people have in captivity is almost infinite. One of the main mistakes people make when they want a primate as a pet is to believe that they have our same needs, especially in superior primates such as chimpanzees. Its expressions are also confused with ours: what the photo shows is not a smile of happiness and what the video shows is not tickling, but an attitude of defense (slow loris have poison in their elbows).

This chimpanzee is not smiling, he is scared. Photo: Photos.com

Many primates live in family groups and the offspring need to be with the mother the first years of life, so that just the simple fact of acquiring a little primate entails the death of all the adults of their family group and psychological problems for the animal. To know the extensive and serious problem of keeping primates in captivity, we strongly recommend reading this post.

SUGAR GLIDERS

Sugar gliders (Petaurus breviceps) resemble a squirrel, but in fact they are marsupials. They have a very specific diet (insects and their depositions, eucalyptus sap, nectar …), they live in the canopy of trees in groups from 6 to 10 individuals and move between the trees jumping up to 50 meters with a membrane that let them hover. They are nocturnal so they yell and call at night. It is evident that it is impossible to reproduce these conditions in captivity, so the majority of sugar gliders die due to nutritional deficiencies.

Sugar glider caged. Photo: FAADA

VIETNAMESE POT-BELLIED PIGS

Although they are a variety of a domestic animal, Vietnamese pot-bellied pigs (Sus scrofa domestica) are small when tey are young, but adults can weigh more than 100 kilos, so it is impossible to keep them in a flat. There have been so many abandonments and they have reproduced so much, that there are populations established in nature. They can reproduce with wild boars and it is unknown if the hybrids are fertile. There are no wildlife recovery centers or shelters for these pigs, so they continue to affect the native ecosystems.

Since actor George Clooney introduced a Vietnamese pot-bellied pig as a pet, the trend to own one quickly spread. Source

RACCOONS AND COATIS

Other mammals that, because of their pleasant appearance, some people try to have as pets. Raccoons (Procyon sp) develop aggressive behaviors when they do not having their needs covered, they are destructive to household objects and have a tendency to bite everything, including people. Currently in Spain and other countries it is illegal to acquire them and it is classified as an invasive species.

In addition to aggressiveness, one of the most common behaviors of raccoons is “theft”. Source

Coatis (Nasua sp) are related to raccoons and, like them, when they grow up they become aggressive if kept in captivity in a home. In Spain, their possession is also illegal.

coatí nasua
The coati, another friendly-looking mammal that can be dangerous. Source

MERKAATS

Merkaats (Suricata suricatta) are very social animals that live in colonies of up to 30 individuals underground in the South African savanna. They usually make holes in the ground to protect themselves and are very territorial. Therefore, having a meerkat at home or in a garden is totally unfeasible. In addition, the climatic conditions (high temperatures and low humidity) in which they are adapted are not the same as those of a private home.

As sugar gliders, their food is impossible to reproduce at home: snake meat, spiders, scorpions, insects, birds and small mammals… Like raccoons, they do not hesitate to bite and are very active animals.

Meerkat with a leash where you can see his fangs. Photo: FAADA

FENNEC FOX

This species of desert fox (Vulpes zerda) has also become trendy as a pet. Although its tenure is still legal, it has been proposed several times as an invasive species.

The main reason why you can not have a fennec at home are the desert climatic conditions to which it is adapted. Living in an apartment causes kidney problems and thermoregulation problems. Also, it is a nocturnal animal. Changes in their circadian rhythm cause them hormonal problems.

Fennec  fox in the desert. Photo: Cat Downie / Shutterstock

Like the previous two species, behavioral problems can turn up and become violent against the furniture or its owners.

ELEPHANTS, TIGERS …

Although it may seem incredible, there are people who have an elephant in the home garden and other people have felines, like tigers. At this point we do not think it is necessary to explain the reasons why these animals have not their needs met and the potential danger they pose to their owners and neighbors in case of escape.

Dumba, the elephant that lives in a home garden in Spain. Photo: FAADA

IN CONCLUSION

As we have seen, a wild animal in captivity will never have its needs covered to guarantee its welfare. Here we have presented the best known wild mammals that are kept as pets, but unfortunately the list does not stop expanding.

In order not to favor animal trafficking and cause unnecessary suffering during the life of the animal, avoid buying wild animals, inform yourself and inform the people around you, denounce irresponsible tenures and in case you already have one wild animal as a pet and you can no longer keep it, contact a recovery wildlife center and never abandon it into nature.

MIREIA QUEROL ALL YOU NEED IS BIOLOGY

 

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How animals see the world?

Have you ever heard that dogs see in black and white? Or that cats can see in the dark? Why we have our eyes in front of the face? And why goats have an horizontal pupil? This article will answer these and other questions about the eyes and vision, focusing on mammals.

HOW IMAGES ARE FORMED?

The eyes are the receptors responsible for capturing light and sending the signal through the optic nerve to the brain, which make the interpretation. Light is an electromagnetic wave as infrared, ultraviolet, X rays, microwaves, etc. In this post we will refer to visible light, that is, the part of the spectrum that can perceive humans and most mammals.

eye parts
Parts of the eye. Source

Basically, the light passes through the pupil. It can regulate the amount of light thanks to the muscles associated with iris (which gives color to the eye). The lens focuses the objects. The image is projected inverted in the retina, to be sent as an electrical signal to the brain.

WHY DO WE SEE IN COLOR ?

In the retina there are two main types of photoreceptor cells: cons and rods. The main differences are:

RODS
  • More sensitive in a few light conditions
  • No color vision
  • Motion-sensitive
  • Less image detail
CONES
  • Activated under conditions of high light
  • Color vision
  • Contrast-sensitive
  • High image detail

That’s why in low light, vertebrates see in black and white and the image is not clear, since the rods are activated at maximum but the cones are inactive. Some primates have three different kinds of cones (trichromatic vision), which correspond to the red, green and blue colour (RGB). Some primates and other animals have monochromatic vision (they only have one type of cone) or dichromatic (two). Some animals have tetrachromic vision, like birds.

The cones are sensitive to different wavelengths, different colors. Photo taken from Colombian Primatological Association

Generalizing a lot, diurnal vertebrates have more cones than rods and nocturnal ones have more rods than cones, allowing them to see better in the dark. But they can really see in the dark?

SEEING IN THE DARK

In total absence of light it is impossible to see, although some animals can detect other radiation such as infrared (snakes) or ultraviolet (bees). In addition to the relation between rods and cones, other factors that improve vision in low light conditions are:

THE CORNEA

The bigger the eye and the cornea, the better use of light. The mammal with the greatest cornea in relation to the eye is the Philippine tarsier (Carlito syrichta ) a nightlife primate.

Philippines’ tarsier (photo: Yeo Kok Leng)

THE PUPIL

Another way to take advantadge of few light conditions is increasing the size of the pupil. According to the shape of it, the control of incoming light is more precise: it is the case of many cats. Compared with a round pupil, the elongated one opens and closes sideways and according to the position of the eyelid, pupil surface exposed to light can be controlled better.

The felines with vertical pupil can open it horizontally and control better the entry light than with a circular pupil. Image of an unknown author, adapted from Aquàrium-Liège Museum

 

THE TAPETUM LUCIDUM

Cats, dogs, bats, horses, whales, crocodiles, cattle and some nocturnal primates have in the retina or behind it a bright layer called tapetum lucidum, which increases up to 6 times the light gathering ability compared to humans. As if it were a mirror, the tapetum lucidum reflects the light reaching the eye to return back to the retina and harness light to the maximum.

Reflection of light due to the tapetum lucidum. Image taken from Exclusively cats

The tapetum lucidum is responsible for cat’s eyes appearing to glow in the dark and cat and dog’s pupils shine in blue/green when light falls upon the eye.

Tapetum lucidum shining on a dog. Photo Mireia Querol

WHY SOME ANIMALS HAVE THE EYES IN FRONT OF THE FACE WHILE OTHERS HAVE THEM ON THE SIDES ?

The position of the eye in mammals can be frontal, like a cat, or in the side, like a rabbit. This means distinct advantages:

  • Binocular vision (stereoscopic): allows a good estimation of distance, but the field of view is smaller. A 3D image is generated. It is typical of carnivores that should focus attention to their prey or primates that should calculate the distance between the branches.
  • Side vision (peripheral): allows each eye to send a different signals to the brain, so it is easier to notice their surroundings having a field of view of about 360 degrees. It is typical of herbivores, which must pay attention to the presence of potential predators .

    Visual field of a cat and a horse. The blind area is smaller in hervibores. Source: Sjaastad, Sand and O. Hove K. Photo taken from Eye Opener

WHY GOATS HAVE AN HORIZONTAL PUPIL?

In addition to the position of the eyes, the shape of the pupil is also related if you are a predator or a prey. Goats or horses have horizontal pupils, while cats like the margay have it vertical.

Pupil of a goat (horizontal) and a cat (vertical) Photo: Wikimedia Commons

Banks  says that “to calculate distances predators basis on stereoscopic vision (works better with a small pupil) and sharpness (works best with a larger one). Vertical pupils are small horizontally and large vertically”.

In the case of terrestrial prey attacked by predators, the tendency of the pupil is being horizontally because “can gather more light and and also reduces the sunlight, which could dazzle “. Exceptions such as rabbits or mice with a circular pupil, are because they have to pay attention also to the sky, from where a bird of prey can attack.

WHAT IS THE THIRD EYELID?

Some animals have the nictitating membrane (“third eyelid”), a transparent or translucent membrane that is used to protect and moisten the eye without losing visibility. Camels, seals and polar bears have it complete, whereas in other mammals, such as dogs or humans remains only reduced.

Nictitating membrane in a feline. Photo by Editor B

IS IT TRUE THAT DOGS AND BULLS SEE IN BLACK AND WHITE ?

Actually dogs and cats are able to detect colors, particularly gray, yellow and blue in softer tones. Cats may be able to perceive more colours.

Visible spectrum by a dog and a human. Source

In the case of bulls, it is also spread the myth that rage against the red colour or see in black and white. Actually bulls have dichromatic vision, like most diurnal mammals, since they only have blue and green cones. Therefore, they can’t see red, but it does not mean they see in black and white.

AND OTHER MAMMALS?

Horses see in blue and red tones. Most rodents see in black and white. Most species of the family of goats, sheeps and bulls see from green to violet. In addition, recent studies indicate that many mammals (especially nocturnal ones), contrary to what was believed, also can perceive ultraviolet radiation: rats and mice, reindeer, possibly cats and dogs, cows, pigs, ferrets, okapi…

We finish with a BuzzFeed video with the simulation of vision of some animals. If you have more questions about animal’s vision leave it in the comments!

REFERENCES

Three felines you might not know

Cats, tigers, lions, panthers… we all know big cats, but what about the small ones? Do you know who are the caracal, the jaguarundi and the margay? Read on to meet them.

WHAT IS A FELINE?

Maybe you have a cat (Felis silvestris catus) at home, but have you ever thinked about what it has in common with a tiger? The truth is that a lot: the similarity among all species of felines is extraordinary and the classification of the smallest ones is difficult .

Felines are the most specialized carnivorous mammals. They live across Eurasia, Africa and America, from deserts to alpine heights. Most are solitary, big climbers (except the larger ones) and many good swimmers.

ANATOMY

With round face and short snout, felines have developed specialized canine teeth to cut meat. They have 5 toes on their front paws and 4 in the back paws, with a curved retractable claw in each to grab prey. Retracted in the rest position, the claws are kept well sharpened. The pads of the feet, surrounded by hair, help them to be silent while walking.

Felines have very acute senses, from a good night vision, good sense of hearing and smell and sensory whiskers .

retracted and extended a feline claw. The domestic cat declawing involves the amputation of the nail and the first phalanx, which can cause serious bodily injury. In many countries it is illegal to be ethically unacceptable.
Retracted and extended feline claw. Domestic cat’s declawing involves the amputation of the nail and the first phalanx, which can cause serious injury. In many countries it is illegal to be ethically unacceptable.

THE CARACAL: THE BEST JUMPER

The caracal (Caracal caracal) lives in Africa and western, central and southern Asia, in semi-desert areas and savannah. It is also known as desert lynx, but is more related to other cats (such as serval and the African golden cat) than with the lynx. It has medium size (60-90 cm long); its lynx appearance is mainly due to hair brushes in his ears, the longest and widest of all felines. Its usefulness is unclear, maybe they can improve hearing, ward off insects or highlight facial expressions as a system of communication between peers. Indeed, its name comes from the Turkish word Karakulak, literally “black ears”.

Their fur is usually brown or reddish and blotchy white belly, although there are melanic individuals (skin and coat with lots of black pigment melanin) as found in other felines, such as the famous black panther, which actually is a melanic leopard ( Panthera pardus ).

 Caracal in South Africa. Photo taken from Blue Project
Caracal in South Africa. Unknown author

Their habits are mostly nocturnal and solitary. The most notable ability of the caracal is their jumps up to 3 meters vertically and catching birds in flight. It is also good climber, so it can prey on nests in trees. Its other dams are small antelopes, rabbits, rodents, etc. and poultry, so it is persecuted for this reason.

Watch a caracal jumping and catching a bird in flight:

According to the IUCN Red List is not generally considered in danger, but as “least concern”, although the Asian subspecies (Caracal caracal schmitzi) has suffered a serious setback. In addition to hunting, habitat destruction is the main threat of the caracal.

JAGUARUNDI: THE RAREST ONE

The jaguarundi or eyra cat (Herpailurus yagouarondi) is distributed throughout the southern United States to South America, in habitats such as tropical forests, wetlands and arid shrublands.

It has small size (9kg), and it seems more a puma or a weasel, with long legs and short tail and ears. The coat is uniform, without spots or stripes, with colors ranging from black, gray, light brown or reddish. Even in the same litter, the pups may have different hues. The dark furs are more common in wooded areas, while clear furs in drier environments.

 Jaguarundi. Photo Kevin Schafer
Jaguarundi. Photo by Kevin Schafer

Unlike other cats of its size, its territories are quite large and are mainly terrestrial, although it moves smoothly through the trees. Their prey are small mammals and birds, but can also hunt on reptiles, amphibians and fish caught in the river banks. It can jump two meters and as the caracal, catch their prey in the air.

Watch the movements and techniques of a jaguarundi hunting from 9:55 minute:

Just like the caracal, it is considered as “least concern “by the IUCN, although populations are smaller than initially thought, since being diurnal is an easily observable species. The threats are the same: prosecution for killing poultry and habitat loss and fragmentation. Fortunately his fur has no commercial value.

MARGAY: THE BEST CLIMBER

The margay (Leopardus wiedii) is distributed throughout Central and South America in forested areas. Similar to ocelots, has a size and weight (40-60 cm long and 3.5 kg) smaller than them. The spotted coat helps them blend in with the environment. These spots are called rosettes and cover the entire body except the head . Each individual has his own pattern of spots, like our fingerprints.

 margay in a tree Stock Wendy Shattil & amp;. Bob Rozinski
Margay in a tree. Photo by Wendy Shattil and Rob Rozinski

 The most striking of margay are their big eyes and tail, very long (up to 70% of their body size). These are adaptations to their nocturnal habits and extreme agility to move through the trees, where it spends most of the time. Their prey are birds, small monkeys, small mammals, lizards, tree frogs and even insects.

The margay special ability is that it can vertically go down tree trunks, with its head down like squirrels do. This is possible because they can rotate 180 degrees the rear ankles. The only other feline able to do the same: is the clouded leopard (Neofelis nebulosa). This feature, along with special claws for climbing and clinging to the branches, allow them to move through the trees with the agility of a monkey: they can even hold on to a branch with only one leg. They are therefore the best climbers among cats.

 Margay down a trunk with the head down. Photo taken from online Terrarium
Margay down a trunk with the head down. Photo taken from Terrarium online

Like caracals and jaguarundis, margays are solitary and they meet only when they have to mate.

The margay is classified by the IUCN as “near threatened and their populations are declining. Unlike jaguarundi, it is hunted for its beautiful fur and for use as pets illegally. The destruction and fragmentation of habitat (forest conversion into farmland) are the other major threat to the margay, who does not tolerate humanized habitats.

We finish the post with images of margay in action from 1:22 minute:

REFERENCES

MIREIA QUEROL ALL YOU NEED IS BIOLOGY