In this week’s Pet Talk, Maneka speaks about the stripes of zebra, squirrel and striped mouse and explains how tigers communicate and about gaining a dog’s trust
How did the zebra and the squirrel and the striped mouse get their stripes?
There are several reasons that scientists have given over the decades:
- a) The stripes allow them to merge into the woodland background, so as to escape predators.
- b) Stripes help in cooling the body from overheating.
- c) Hunters find moving striped objects difficult to target accurately — the so called “motion dazzle confusion effect.”
However, this current theory has the most support: that parasites — mosquitoes and flies — find it impossible to attack striped animals, while they can feast on uniformly coloured animals. Dr. Tim Caro of the University of California, Davis and Dr. Susanne Akesson from Lund University, Sweden, point out that horse flies and similar parasites, which feed on the blood of animals, are attracted to light that is oriented in a particular direction (polarisation) or glare. This glare attracts and helps these insects zone in on the target. Dark skin polarises light better than brown or white. But if the skin were striped dark and white, it becomes less attractive to the bloodsucker bugs. Akesson has argued that the black and white pattern “is ideal in its functions of disrupting this signal of reflected polarized light” and, in effect, is camouflaged to flies as well as big cats.” (A science writer, who covered this research paper, has suggested that we use Zebra striped wall paper to shoo away mosquitoes and flies. Worth trying!)
Dr. Caro and colleagues studied in detail seven different members of the equid family across Africa and Asia — On one hand studying their skin colouration and striping, and on the other the location and prevalence of blood-sucking flies, such as the horsefly and the tsetse, across this broad region of Sub-Saharan Africa. Their paper, “The function of zebra stripes,” which appeared in the journal Nature Communications, finds the strongest connection between the biting fly annoyance and the number, spacing and intensity of stripes in the face, neck, belly, rump, flank and legs of the striped equids.
In effect then, stripes evolved in African equids largely to protect them from the blood sucker insects which abound and thrive in the African tropics. Stripes fool these bugs, perhaps by the disruption of the polarisation of light falling on the striped pattern on the hair and skin. Is this why zebras or striped squirrels are not found in the U.S., Northern Europe or Russia? Neither is the climate there welcome to such bloodsucker insects.
What is a treatment for dog ear mites?
There are several types of mites that can live in your dog’s ear, but the most common are Otodectes cynotis — tiny, eight-legged parasites that feed on the wax and oils in a dog’s ear canal. An individual mite has a three-week life cycle, and is barely detectable by the naked eye. Causing irritation and inflammation ear mites can infect the external and internal canal, and lead to more serious skin, or ear infections, if left untreated. Infection usually produces a characteristic dark discharge; in some cases, the ear canal can become entirely obstructed by this coffee ground-like debris.
Highly contagious, ear mites are most common in outdoor cats, which can infect their canine companions. They are most often passed from pet to pet in casual contact at home or outside. Humans are generally immune to ear mites.
General symptoms of ear mites are: i. Excessive scratching and rubbing of ears; ii. Head shaking; iii. Black or brown waxy secretion; iv. Strong odour; v. Inflammation; vi. Obstruction of ear canal with coffee ground-like discharge.
It is important to bring your dog to a veterinarian for an accurate diagnosis. Your veterinarian will take a sample of ear discharge and evaluate it microscopically to confirm the presence of ear mites. Avoid self-diagnosis, since certain types of bacterial infections can mimic the symptoms of ear mites.
- Ear mites can be treated with products your veterinarian will prescribe, that are applied directly in the ear, or parasite medications that are applied right to the skin.
- If the ears are infected, or have a build-up of debris, gentle cleaning may be required with cotton and a canine ear cleaner. (This may require sedation, depending on the dog’s temperament and the severity of build-up.) Your veterinarian may also prescribe anti-inflammatory drugs, or an antibiotic, to resolve infections.
iii. A dog will start to feel relief soon after treatment begins, but please complete the full course of treatment, and remember that all animals in the household need to be treated to ensure full eradication.
How do tigers communicate?
Tigers communicate using vocal sounds, body language and marking on trees. Although they live fairly solitary lives, they do get together occasionally, and it is during these interactions that they communicate with one another. Communication helps to warn of predators or other danger, establish territory and form social bonds.
One of the ways tigers communicate is by scent. Males and females, and mother lions and cubs, often rub their faces together as a way of transferring their scent to each other. Male tigers often leave their scent by urinating on objects, such as trees, which marks their territory.
Another form of communication is vocal communication. Mother tigers call their young by using soft moans to summon them. The groan is a non-threatening form of communication. When a tiger roars, it may be used as a sign of danger, or as a warning to other tigers to back off.
Like all cats, tigers are masters at visual communication. They use different forms of body language to communicate different emotions. For example, a defensive posture is one where a tiger will lay its ears flat and bares its teeth. A relaxed tiger will have its ears and tail in an upright position.
How do I gain a dog’s trust?
Dog socialisation is different from human socialisation. When dogs meet, they say “hello” and shake hands in a different way from humans. If you are meeting a dog for the first time, you will need to gain his trust by using dog language, rather than human language. If you are trying to gain the trust of a new puppy or dog, you will also need to use certain techniques to allow the dog to see you as a friend and owner, rather than a threat.
- Remain calm when you first meet the dog. If you are interacting with your new dog for the first time, or if you are interacting with a dog you have never met before, avoid the temptation to approach the dog in an excited state. Instead, project calm and relaxed energy when you meet the dog. Act calmly and greet the dog softly.
- Acting excited can make the dog excited and lead to an aggressive greeting, like jumping up on you or barking at you. This can also trigger the dog’s fight or flight instinct, as a stranger approaching the dog with high energy can feel like a threat to the dog.
- Keep your distance. Respect the dog’s space by addressing the human with, or owner of, the dog first. Ignore the dog and avoid standing too close to the dog. You should allow at least four feet between you and the dog. This will give the owner time to give you permission to interact with the dog.
- Get down to the dog’s level. Ask the owner if you can interact with the dog. If they say yes, approach the dog from the side, never from the front. Kneel down next to the dog, facing the same direction as the dog is facing. This will show the dog you are occupying his personal space, but you are not being confrontational. Do not make eye contact and hold your hand down in a fist.
- Allow the dog to approach you. Rather than putting your hand out to the dog, let him respond to you by sniffing your hand. If he remains calm, you can pet the front of his chest.
- Do not touch an unfamiliar dog from above, or pat his head. If the dog licks your hand, he has accepted you. But if he turns his head away or does not pay attention to you, he is not interested in interacting. Avoid taking this personally. Instead, interact again with the owner and try again when you next meet the dog.
- Use a treat. If you are trying to get a dog to trust you as his new owner, you can integrate treats into this process by allowing the dog to approach you and take a treat from your hand. When the dog takes the treat, say “Good dog.” After a few sessions of taking the treat from your hand, the dog may touch your hand before taking the treat. Once he starts to do this, you can try to pet the front of his chest and under his chin. It can take time to gain the dog’s trust, and the more you meet or interact calmly with the dog, the more likely he is to trust you. Progress slowly, from using the treat to petting the dog, to avoid scaring him. Once he allows you to pet him, you have started to build trust between you and the dog.