20.1e – Horses and Humans

Did you hear the one about the pessimist’s horse? It was a neigh-sayer. (Photo by Thurner Hof)

We don’t really know for certain when the horse was first domesticated, but evidence suggests it was sometime around 3500 BC in the Eurasian Steppes, which is to say, somewhere in the region of the modern day Ukraine and Kazakhstan, where semi-nomadic and sometimes cultures once flourished. The earliest evidence of this domestication comes from bones. Around that time horse bones began to appear in human grave sites, and horse skeletons found from that era show evidence of having bits in their mouths, used for control by humans.

The date isn’t what really matters. Humans have admired horses for a very long time, and some of our earliest cave art from more than thirty thousand years ago depicts wild horses that we once hunted for food. Eventually we began to work out how to tame wild horses for our own use, likely at first for riding during hunts so that we could more easily catch and kill wild horses.

The use of domesticated horses spread throughout much of the old world. They were used to pull chariots as early as 2000 BC. We began to control their breeding and created many new varieties based on qualities we preferred, such as size, color, temperament, and speed.

Horses quickly became invaluable partners in the advance of human societies and civilizations. On horseback our limited footspeed is multiplied several times, giving humans easier and wider access to the world. Horses became instrumental not only for transportation, but also for war, where the development of mounted cavalry changed the face of battle and became a dominant form of attack until very nearly our own time. Only the development of heavy artillery and tanks within the past 200 years has supplanted the horse from the forefront of human warfare. It is no exaggeration to say that nations have been won or lost on the strength of their horses.

But as much as we admired them for their ability to move us about quickly, we also came to love them as companions. Horses are intelligent creatures, capable of learning and retaining a great deal of information, and like dogs they have natural social skills that let them more easily fit in with humans. Horses are used to living in groups, and domesticated horses are willing to accept humans as herd leaders, to work with us and enjoy our company as we enjoy theirs.

Today, though there are few wild horses remaining and though the direct ancestor of the domesticated horse, the tarpan, is extinct, there are 59 million domesticated horses in the world. We use them in sports and for leisure, and we also still use them for work even though their dominant role has declined. Horses live 25 to 30 years in many cases, and the oldest horse on record made it to 62, making them longer-term companions than our other most popular pets.

The biggest horses and the tiny ponies all come from the same original domesticated ancestors. (Photo by arjecahn)

Horses aren’t the only ones in this family that we’ve domesticated. Humans also domesticated the ass around the same time, likely in the Middle East, and these domesticated asses we call donkeys, possibly because we got tired of saying “ass” all the time.

A donkey is a different animal from a horse. Not only are they smaller and a bit slower, less suited for riding or using in war, but donkeys do not form permanent herds in the wild. This means that their social instincts are not as highly developed as a horse’s, and donkeys are known for being more stubborn. Befriend a horse and you can work to convince it to do just about anything for you; befriend a donkey and it will work for you, but good luck making it do anything it doesn’t want to. A loyal and well-trained horse will give its life for a human if asked to, running itself into the ground or through fires or along dangerous paths, but a donkey typically cares about its own skin more than it cares about what you want.

While all the glorious roles in human history have gone to horses, donkeys have been stuck with the less flashy but no less important grunt work. They have been used as pack animals for thousands of years, especially in dry areas or regions with very rocky ground. Donkeys are still used as important workers in many less developed countries — hauling goods, providing transportation, and supplying raw strength for mechanical operations. Donkeys need less food than horses, and can be more steady workers as long as you don’t try to make them do anything fancy. There are about 41 million domesticated donkeys in the world today, most in Africa and Asia.

“Couldn’t you have made one of the other 41 million wear this suit?” (Photo by Sue Sleaford)

Horses and donkeys can be cross-bred together (as can every different member of the horse family to varying degrees) to create an infertile hybrid called a mule. Mules are not a true species, for they cannot reproduce except in very rare circumstances, but they gain some of the best characteristics of both parents. Mules are said to be patient and steady like a donkey, but strong and loyal like a horse. They are also quite intelligent.

We don’t use mules as much as we used to; they’ve largely been replaced by machines. But there are still some jobs that mules do better than anything else can, and even the modern United States Army uses mules for supply transportation through rugged areas of Afghanistan.

Whether used in peace or war, for transportation or companionship, the various domesticated members of the horse family have helped shape our development for thousands of years. We are better people for their partnership, and they will continue to work with us and to carry our burdens for many long years to come.

20.1a – The Equids

The horse family, from A to Zebra. (Photo by Joachim Huber)

The first and best-known of the odd-toed hoofed mammal groups are the equids, better known as the horses. Horses first evolved in North America as small hoofed animals about the size of a fox, and over more than 50 million years they went through a number of forms as they became larger, faster, more social, and more intelligent, all as ways to survive against predators.

Throughout the past 50 million years there have been a lot of different types of equids; there have been as many as 37 different classifications of them, but today only one survives. In that one surviving group, which once had 22 species, there are now only seven still living.

Of these seven, one is the horse, three are asses (also known, in a name that gets less snickering, as donkeys), and three are zebras.

All equids are roughly a similar shape, with long legs that are excellent for running. Even though all members of the order Perissodactyla have three toes, in equids the two outer toes have receded almost to the point of non-existence, and the animal runs on only one very large toe that is wrapped in a hoof.

As a plant-eating prey species, equids have developed a number of anatomical and social adaptations to help them survive. The first, of course, is running, but an equid can also use its powerful legs to strike an enemy when forced into a fighting situation, which can end very badly for the thing being kicked.

They have good hearing and can rotate their ears in any direction, even different directions at the same time, to locate the source of a sound. But their eyes are the real wonders.

Equids, particularly horses, have the largest eyes of any land mammals, including elephants. The eyes are set on the sides of the head, which is something you will notice with many prey species. This is to allow the widest possible field of vision so that they won’t be surprised, and indeed it is difficult to surprise an equid. Their eyes can look in almost every direction at once — everything except directly behind them. Their ability to focus directly in front of them is limited by the position of their head, but they can still see with peripheral vision even when not focusing.

It’s hard to catch an equid napping too. They need far less sleep than humans, and get it in a different way. While an equid typically needs to lie down and get a few hours of deep sleep once every two or three days, in the meantime it sleeps in short, shallow bursts while standing up. Equids have special locking mechanisms in their legs that they can engage in order to fall asleep without falling down. They might only sleep for 15 minutes like this, dozing lightly and easily able to wake up and run at any sign of danger, and then they will be refreshed.

While one horse sleeps another has got its back. Teamwork! High five! Er, I mean … high one? (Photo by Mikel Ortega)

Equids also live in herds for the sake of safety. It’s even easier to grab a quick standing nap when you have others looking out for you, and an animal in a group is less likely to be killed than an animal alone. Equids have a complex social system that can include hierarchy, succession, leadership, play, and communication. Horses and zebras form permanent herds, while asses form herds that are only temporary.

In the following articles we will look at each of the wild species in this family, and will then examine the domesticated horse and donkey.

13 – The Book of Lagomorpha

Pictured: not a rodent. (Photo by JJ Harrison)

The lagomorphs used to be considered rodents, or at least very closely related to rodents, but we now know that’s not the truth. There are two different basic types of lagomorphs, and they’re both more removed from rodents than one might guess. They are the rabbits and hares in one family, and the pikas in another.

Like rodents and hyraxes, lagomorphs have teeth that never stop growing, meaning that the animal has to keep chewing on things to keep the teeth from growing too long. This guarantees that they always have enough tooth to get the job done, but it also guarantees that they will always be chewing on something and potentially making a nuisance of themselves.

Where they diverge from rodents is that they have four ever-growing cutting teeth in their upper jaw, while rodents only have two, making a lagomorph the ultimate chewing machine. Lagomorphs also only eat plant matter, while rodents will eat pretty much anything.

So they’re not rodents, and not actually all that closely related to rodents, but it took scientists until the early 1900s to figure that out. But none of that is really what makes lagomorphs interesting.

They live practically everywhere in the world. Pikas have adapted to rocky areas, while rabbits and hares have adapted to live, well, pretty much wherever they want. They can survive just as well in distant wilderness as they can in the heart of our cities, and once a wild rabbit population takes hold, good luck stopping it. Australia has learned this to its sorrow, as we will soon see.

In all there are about 90 species of lagomorph, 30 of which are pikas. Only the rabbits and hares have developed the long hind legs that let them bound quickly across the land, but pikas are fast and elusive creatures in their own right, which you will not if you ever hear one in the mountains, look around, and can’t for the life of you find it. In the next series of articles we will look at each family individually, and at some of the coolest speices within each group.

5.2a – The Microbats

They may be micro, but these bats do it all and they do it everywhere. This is a Mexican long-tongued bat. (Photo by Ken Bosma)

The microbats may be in general much smaller than the megabats, but what they lack in size they more than make up for in numbers. Simply put, there are an awful lot of them. They are found everywhere in the world, often in enormous numbers, and play a critical role in the control of insect populations.

However, size is not one of the distinguishing characteristics between the two groups of bats, as we have learned before. The biggest difference, though there is an exception, is that microbats use echolocation to “see” in complete darkness, while megabats do not (except for the Egyptian fruit bat, which is the noted exception). There are a few other small differences, but the only other interesting one is that microbats are not furry like most megabats are. Instead, microbats have stiff guard hairs, or almost completely lack hair altogether.

While some few microbats will eat fruit and nectar, and while still fewer eat fish or feast on the blood of living animals, the vast majority of microbats eat insects. This is where echolocation comes in handy. Many insects are active at dusk, which is when microbats swoop out of their roosts to devour them, and echolocation lets them locate their prey with little or even no light to see by. Since they have little need for them, most microbats have very under-developed eyes, though none are truly blind.

Otherwise microbats get along much the same as megabats do, flying via the same mechanism and roosting in dark places during the day, often in caves or tree hollows or unused spaces in human buildings, or really anywhere the sun don’t shine.

Well, no, not THAT place the sun don't shine. You couldn't even fit this colony of pallid bats in there. (Photo by Geoff Gallice)

There are quite a few distinct microbat families, mostly named for a defining physical characteristic. We will look at some of the more interesting individual bat types, but we won’t be examining every single family, so a brief overview of the microbat family tree might be of interest to you here.

There are 17 microbat families, which if you are keeping track is the largest number of families in one group that we’ve seen so far.

1. The sac-winged bats, of which there are 51 species, live in tropical areas. They get their name from sac-shaped glands in their wings, which release pheromones to attract mates. They don’t mind light as much as many other bats do. This family is home to the ghost bats, which are entirely white.

2. The mouse-tailed bats, of which there are five species, found in northern Africa and southern Asia. Unlike many other bats, their wings are not connected to their tails, and instead hang free, thin, and mouse-like, almost as long as the entire rest of the bat. In Egypt these bats are known to roost inside the pyramids. They live in groups of at least a thousand bats.

3. Owning a family all to itself is the Kitti’s hog-nosed bat, also called the bumblebee bat. It is the world’s smallest bat, only about an inch long, and is one of the world’s two smallest mammals. It lives in southeast Asia.

4. There are about 70 species of horseshoe bats, so-named because their noses look sort of like tiny horseshoes, and they use this strange nose to help with echolocation. They live in Europe, Africa, Asia, and Australia.

5. The slit-faced bats have 16 members, found in Africa and southeast Asia. Their faces have a long slit running down the middle, right between the eyes, and they rely more on their ears and less on their echolocation compare to other microbats.

6. There are five species of false vampire bats, found in Africa, southern Asia, and Australia. They have no tail and look sort of like vampire bats, but they eat only insects and small scurrying critters.

7. The vesper bats, also called the evening bats, boast a remarkable 440 species, which is almost ten percent of all mammal species right there. These are the classic small bats, living in caves and emerging to eat insects, though some eat fish or small birds. There are big vesper bats and small vesper bats, and some groups roost in numbers of up to a million.

8. There are about 100 species of free-tailed bats, most of which are excellent at flying and are able to catch insects in full flight. They are found everywhere except Antarctica. They get their name because their tail is not fully connected to their wings, but instead can pull the wings into different shapes for better flying abilities. Some species in this family roost in enormous colonies of up to 50 million bats in a single cave.

9. The pallid bats are not well classified, but there are about 14 of them. They have large eyes, large ears, and pale hair. They are notable for being good at controlling their internal temperature.

10. The 11 species of funnel-eared bats are found in central and South America. As you would expect, they have broad funnel-shaped ears, though the bats themselves are quite small.

11. There are only two species of sucker-footed bats, both found in Madagascar. Like much on that island, not a great deal is known about them, but they have small suction cups on their wrists and ankles at they use to attach themselves to smooth surfaces for roosting. Isn’t that weird?

12. The disk-winged bats are only four members strong, found in central and South America. They also have small suction cups on their limbs, though here they are called disks for naming purposes.

13. There are two species of smokey bats that live in central and South America. They have very small, useless thumbs and funnel-shaped ears.

14. There are only two bulldog bats, also called the fisherman bats, and we will look at them in more detail soon. They live in central and South America, and the larger of the two catches fish from the water.

15. Only one type of New Zealand short-tailed bat remains. Found on that eponymous island, they spend most of their time on the ground instead of flying, and have claws adapted for digging and climbing. They eat whatever they can get their long tongues on.

16. There are ten ghost-faced bats, which have strange faces with leaf-like projections on their lips. They live in both North and South America.

17. The leaf-nosed bats are found in central and South America, and there are 192 species, including the infamous vampire bat, on which more is soon to come. They have large noses.

This fringe-lipped bat is part of the leaf-nosed bat family, and has a face only a mother could love. (Photo by Felineora)

5 – The Book of Chiroptera

The world's one and only high-flying mammals. (Photo by the US Bureau of Land Management)

The order Chiroptera (pronounced kai-ROP-tuh-ruh) is by far the largest order of mammals in the world. These are the bats, and one in every five species of mammal is a bat. To be more precise, there are 1240 bat species in the world. While this is less than nothing compared to some of the non-mammalian orders, as far as mammals go this is an awfully big number. Put plainly, there are a lot of bats in the world.

They can be found everywhere except the polar regions, which is not surprising when you realize that they are the only type of mammal capable of true sustained flight, meaning they can cross bodies of water, mountain ranges, and nearly any other obstacle to spreading out as far and as wide as possible.

As a note, don’t be fooled into thinking any other type of mammal can fly, such as the flying squirrel. It and other mammals like it merely glide for short distances, while bats truly fly, just like birds.

Well, not “just” like birds. Bats developed the ability to fly separately from birds, and they did it just a little differently. While birds flap their entire forearms to fly, bats only have to move their hands up and down. The entire wing structure on a bat is formed from elongated fingers and a thin, leathery covering known as patagium.

There are two major divisions in Chiroptera — there are the megabats and the microbats. This terminology is not entirely about size, as there are large microbats and small megabats, but the megabats are for the most part bigger. The real difference is that most megabats eat fruit, while most microbats use echolocation to hunt insects. There are exceptions, but we will come to them in their turn.

The microbats and megabats are sufficiently different that some researchers once believed they had evolved separately, each learning to fly on its own, and it was even theorized that the megabats may have evolved from monkeys. Modern genetic research has confirmed however that mammalian flight evolved only once, and that the microbats and megabats split off from a common flying bat ancestor a very long time ago.

A face like this could only have evolved once. This is an Egyptian slit-faced bat. (Photo by Susan Ellis)

You may think that bats are creepy pests, but they are really no different than birds that happen to come out at night. They get a bad reputation because they like to live in dark places such as caves and attics, and because of vampire stories, but most bats are relatively harmless. In addition, they are an important species on a global level for humanity. By consuming vast numbers of insects, bats reduce the need for pesticides in agricultural areas. Without bats, growing enough food for humanity would be much harder. In fact, some people even build bat houses to attract bats to their property, so that their insect population will decline.

Bats are famous for their echolocation, which allows them to hunt in the darkness, but only microbats possess this ability. This echolocation works similar to that of the toothed whales, acting like a radar. The bats emit a near-constant stream of ultrasonic sound that humans cannot hear, and can quickly adjust to their surroundings based on the picture formed in their brain from the echoes that return to them. A bat does not fear darkness, for it can fly confidently in pitch black conditions without worrying about running into anything.

This is good for microbats, because they have very poor eyesight. There is no need for it when you sleep in the day and hunt at night. Despite the saying “blind as a bat,” however, microbats are not actually blind. They can see you, they just can’t see you very well. However, one disadvantage of echolocation is that it doesn’t work very well in rain. Bats stay indoors when it rains, because the falling drops are hell on their ability to figure out their surroundings based on echoes.

Interestingly, there are two types of moth that have developed very specific defenses to bat echolocation. One type produces its own ultrasonic signal that either confuses the bat by jamming the airwaves or acts as a warning. Another type of moth has an automatic response to feeling a bat signal bounce off it, sending it into herky-jerky evasive maneuvers.

Bats are excellent at flying. Though they do not go about it in quite as beautiful a way as birds, they have advantages that birds do not. Bat wings are thin enough to allow for quicker and sharper turns than most birds can make, and the surface of the wings is also extremely sensitive to touch. This means that bats can sense how the air is flowing around their wings and adjust their fingers to create a more efficient wing shape in response.

Some bats are solitary while others can live in colonies a million strong that nest in large cave structures. Some bats hibernate in the winter, either in caves or after migrating to a winter sleeping ground.

These three neotropical fruit bats, roosting on the underside of a large leaf, make a very small colony. It's light out, so they're not happy to see you. (Photo by Leyo)

Bats that eat must also defecate, and bat dung is known as guano. Guano is very rich in nutrients, and is mined from caves for use as fertilizer, yet another way in which bats help out human agriculture. As a fun fact, you should know that during the US Civil War guano was used to make gunpowder, meaning that soldiers killed one another with bat-poop-propelled bullets.

Unfortunately, bats can spread diseases such as rabies, SARS, and several viruses, but the percentage of bats carrying diseases is typically quite small. Rabies is not a major problem, but most rabies cases in the United States are caused by bat bites.

While western cultures often associate bats with darkness and evil, there are places where bats are considered sacred, places where bats are lucky, places where bats are a symbol of happiness, and even places where bats have been worshiped as gods. It’s all in your perspective.

As one final interesting fact, you should know that bats apparently cannot synthesize Vitamin C. No one really knows why, or what this might mean, but I’m willing to bet it drives them batty.

4.2h – The Beaked Whales

A nose in need is a nose indeed. (Photo by Soler97)

The final group of toothed whales can barely be said to have teeth at all, and are also the most mysterious and least-known of all whale families.

So what’s the deal with beaked whales, and why are they so mysterious? There are 21 known species of beaked whales, but we know very little about very few of them, and some of the species are only known from dead bodies that have washed ashore and have never been seen alive. This is because beaked whales spend most of their life far beneath the surface.

Smaller than a baleen whale but bigger than a dolphin (10 to 30 feet long on average), beaked whales are among the world’s best divers. They can hold their breath for more than an hour, and often dive deeper than 1500 feet in search of squid and fish. When they surface for air they do not linger; after taking a new breath, they slip back beneath the water for another extended dive. As such they are rarely seen by humans except when rising to the surface in large groups.

As toothed whales they have echolocation, and use it to find prey in the darkness of deep waters. However, the beaked whales for the most part only have one or two pairs of useless teeth, more like tusks, not nearly enough to chew with. To make matters stranger, only males grow these few teeth, and females grow none. It is believed that females pick a mate based on the size and shape of his teeth, and these curious chompers are good for nothing else at all.

How do they eat all those squid and fish, then? The short answer is, they suck. The longer answer is, a beaked whale will catch prey in its mouth, clamp down, and then pull back its tongue while opening its throat, creating suction and pulling prey, likely still alive, down into the stomach, like some sort of thick, bulbous spaghetti.

These gulping, sucking whales are found throughout the entire world, from polar ice cap to polar ice cap in all of the oceans, but we have only managed to study a few of them because of their secretive nature, and have no idea how many there might be. It has been said that we know more about the surface of the moon than we know about our own deep oceans, and this is not an exaggeration. The oceans are so big, so deep, and so dark that it takes forever to explore and study anything that lives there.

Even though we don’t know much about them, unfortunately we have found a way to accidentally harm them. It has been noted that naval sonar tests and exercises tend to coincide with incidences of beaked whales stranding themselves on beaches or washing ashore, often with internal bleeding and damaged organs.

It is believed that intense sonar distresses the beaked whales as they rise from the depths for air, causing them to rise too quickly. Just like people, if they rise up from deep water too quickly beaked whales will get, essentially, the “bends”, which can cause internal damage. For this reason beaked whales normally rise very slowly when coming up for air. When the sonar frightens them into rising too quickly, they become injured and either wash ashore or become confused and disoriented, running aground and dying. However this is an unproven idea, and more research is needed to determine if and exactly how sonar is affecting these whales.

4.2f – The Sperm Whale

The world's biggest predator. (Photo by Cianc)

If you think that the sperm whale is something that teenagers would snicker about, then clearly you need to learn that it is actually one of the strangest, most fearsome, most interesting toothed whales in the waters.

Growing up to 65 feet long and weighing as many as 60,000 lbs, the sperm whale rivals many of the baleen whales in sheer size. But as a toothed whale it is a hunter, not a filter feeder. Sperm whales are known for their unique shape as well, with an enormous, long, barrel-shaped head that takes up much of the animal’s length and seems out of place compared to its relatively smaller mouth. The head is so big that early scientists guessed that it used its head as a battering ram.

That’s not quite true, though the sperm whale is a fierce fighter and has been known to attack whaling ships that threaten it. In one famous case, which inspired the novel Moby Dick, a male sperm whale sank an entire whaling ship that attacked it. Moby Dick himself was a sperm whale.

But let’s back up. How on earth did it get that ridiculous name?

Sperm whales produce a white, waxy substance from their heads, known as spermaceti. While it sounds like a particularly unwholesome type of pasta, people used to think this was the whale’s sperm, hence the name. In fact, however, spermaceti appears to help with echolocation.

Ah, yes. Even though the sperm whale is gargantuan compared to most of the other toothed whales, it can use echolocation just like they can. And since it can dive up to two miles beneath the ocean, where there is no light, it needs some pretty good echolocation to find prey.

That’s where the spermaceti comes in, and also an explanation for the creature’s massive head. Spermaceti is produced in the head by an organ in the nasal area, which you will remember is the blowhole in whales. Well, it turns out that the sperm whale makes use of its second nostril, using it to make echolocation “clicking” sounds that are among the loudest natural sounds in the world.

The sound energy travels forward, reflects off an object, and returns to the whale. The spermaceti floating around in the whale’s head helps focus the sound waves and is part of a system that reflects the sound back and forth in the whale’s head to create an incredibly accurate picture. It is believed to be the best natural sonar system in the world.

The spermaceti is also believed to help the whale make its deep dives. When diving into cold water, the waxy substance hardens and the whale becomes less buoyant, making it easier to sink. When the whale swims back up to the surface, the warming water causes the opposite effect and helps the whale bob back up to the top again.

In addition, the enormous head houses the world’s biggest brain, hands down, no contest. A sperm whale’s brain weighs about 20 lbs, but the animal is not considered as intelligent as dolphins.

That is all a very long way of explaining a very simple thing — sperm whales have excellent echolocation. But what do they use it for?

The answer is squid. The reason sperm whales are one of the most fearsome hunters in the world is because of the prey they take on. They will not only eat normal little squids, they will dive into the darkest ocean water and use their natural sonar to find the biggest, baddest squid on the planet, the giant squid and the colossal squid.

There aren't many good free-to-use photos of sperm whales, so here is a picture of a piece of sperm whale skin with scars on it, caused by the suckers of giant squid. (Photo by NASA)

The colossal squid, the world’s biggest known squid (though some believe there are larger we have yet to discover), is up to 45 feet long with dangerous, clawed tentacles. Sperm whales will fight and kill these squid when they can, and many sperm whales have been found with sucker scars on their skin and giant squid bits in their stomachs. But a fight between these two giants of the sea has never been witnessed by human eyes.

Sperm whales were historically hunted not just for their meat and oil, but also for their spermaceti and for a substance known as ambergris. Ambergris is a solid, waxy substance that was used, as with so many vaguely yucky animal products, in perfume. It is produced in a sperm whale’s digestive system when it swallows a squid beak that is too large to pass through easily. The beak rubs against the sperm whale’s intestines and causes the production of ambergris, which can help dislodge the stuck beak. That is both marvellous and strange. Ambergris can be taken from a dead sperm whale, but is also expelled both in the feces and out the mouth of a sperm whale and can simply be found floating in the ocean, a grey lumpy wax. Some single lumps can weigh up to 100 lbs.

To make this even weirder, you should know that King Charles II of England was said to love eggs and ambergris as his favourite meal. Nothing starts the day better than unfertilized chicken babies and squid-induced whale poop.

It is estimated that there were once more than one million sperm whales in the world’s oceans, and from the early 1700s to the mid-1900s humans killed most of them — about 900,000 of them, at an estimate. With such large numbers still remaining, however, the sperm whale did not come as close to extinction as many other whales, and there are believed to be hundreds of thousands alive today. They are now protected and only hunted in very small numbers by certain nations.

Female sperm whales are much smaller than the enormous males, and sometimes fall prey to killer whales. Large groups of killer whales can sometimes overwhelm a female sperm whale, and at the very least they may try to separate a calf from the group. Female groups can form defensive circles around calves, with their tail flukes pointed out to swat at killer whales, a similar strategy to that employed by the muskox against wolves on land.

In one final interesting note, some scientists believe that a sperm whale’s echolocation clicks are not actually effective at finding squid. It is theorized that squid may be too full of water to effectively bounce sound back at the whale. Instead, these scientists believe, the loud clicks may be designed to simply stun smaller and medium-sized squid into submission by battering them with repeated waves of sound. This is a lovely idea, but it has not been proven, and no one has explained how they are able to find squid in the first place if not by their echolocation.

Sperm whale distribution.

4.2c – The Killer Whale

The ocean's smartest, smoothest predator. (Photo by Minette Layne)

The killer whale, also commonly known as the orca and sometimes as the blackfish, is found throughout all of the world’s major oceans and most of its seas. As a member of the dolphin family, it is not only one of the best predators on the planet, it is also one of the most intelligent animals anywhere, and occasionally one of the most misunderstood.

To begin, the name “killer whale” is both appropriate and inappropriate at the same time. It is appropriate in that the killer whale is indeed both a killer and a whale. It is an absolute apex predator, able to kill almost anything in the ocean and naturally preyed upon by nothing at all. Killer whales not only eat fish, they can and do also kill — take a deep breath before you start this next bit — seals, walruses, otters, turtles, dolphins, porpoises, penguins, gulls, rays, sharks, baleen whales, squids, sperm whales, sea lions, cormorants, deer, and moose.

If you saw some animals on that list that don’t make sense, fear not, let us elaborate. Not only can killer whales catch birds that are close to the water, they can and will catch and kill large land mammals, such as deer and moose, that try to swim between islands, such as in the northwestern United States. Killer whales hunt in cooperative groups, and are capable of overwhelming and killing large whales. Though they will often go for whale calves instead of adults, separating the calf from its mother and drowning it, they are also capable of taking on fully grown whales.

When it comes to sharks, killer whales get clever. Sharks are dangerous animals, but many of them have an essential weakness — tonic immobility. This is a defensive mechanism in sharks that makes them automatically play dead, inducing uncontrollable paralysis in their bodies when they are threatened in specific ways. Killer whales have figured out how this works, and can kill even large great white sharks by attacking and flipping the shark upside-down in the water, inducing paralysis. With smaller sharks, killer whales will sometimes simply hold them still until they drown, as sharks can only breathe when moving forward.

Not only do killer whales hunt an enormous variety of animals, the do so with a number of different strategies. On top of the ones already mentioned, they will strike with their tails, leap from the water to fall on prey like some sort of professional wrestler, head-butt prey into submission, and two additional abilities that are downright scary in their cleverness.

Killer whales can hunt seals on icebergs using a technique called wave-hunting. Part of the group will wait on one side of the iceberg while the others go around to the back side and charge the iceberg along the surface, pulling up at the last moment to send a wave of water over the ice, washing seals or penguins or anything else into the water where the rest of the killer whales wait. I don’t know about you, but I just got a little chill in my spine.

And that’s not all. If you think being on land makes you safe, you might want to think again. Killer whales have figured out that since they breathe air, they don’t actually need to restrict themselves to the water. They will literally throw themselves up onto a sandy beach on purpose to grab seals, using their strength and tail to wriggle back down into the water once the prey is caught.

Wherever you go, the killer whale knows how to find you. (Photo by the National Science Foundation)

If you’re seeing the picture I’m painting here, you will see that killer whales are incredible, intelligent hunters, powerful and creative and just plain unstoppable. But in another way their name does them an injustice. You see, we named them killer whales because we thought they were evil and that they would kill humans as well. Neither is true. Wild killer whales have never once been documented killing a human being, and they pose us absolutely no threat. Only captive killer whales have ever injured a human. In addition, in a world where everything has to survive somehow, their strength and intelligence are much more awe-inspiring and admirable than evil or frightening. They are remarkable creatures.

Their intelligence does not end in the realm of hunting. Killer whales live in complex, tight-knit family groups that rival those of elephants and primates, and they pass knowledge from generation to generation. The beach-jumping hunting technique described above is not a natural behaviour, and it takes years for a mother killer whale to teach her calf to perform this method safely so that it will not get stuck on land. They have also figured out how to pluck fish off fishing lines, annoying fishermen to no end, and have even been known to outsmart attempts to thwart this practice. Sadly, in the traditional human fashion, we have at times in history taken to outright killing them because of this.

Killer whales also have one of the closest things you can find in the animal world to language and culture. They have a variety of vocalizations that we don’t know the meaning of — not enough to make a full language, but they are almost certainly communicating with one another. The impressive part is that each and every family group of killer whales has its own unique language, known as a dialect. No two groups has the same vocalizations, and mothers directly teach the group’s dialect to their young, who are not born knowing it. Closely related groups of killer whales have dialects that are more similar than those of unrelated groups. This is a distinct, learned social behaviour that is passed on from generation to generation.

Killer whales don’t have much to say yet, as they only possess about a dozen unique vocalizations per group, but they are almost certainly learning to talk to each other, and human language probably started in a very similar manner.

Often seen leaping out of the water when swimming or hunting, killer whales are one of the fastest marine mammals, capable of speeds up to 35 miles per hour. Leaping from the water actually helps them go even faster. That may seem strange, but air is much less dense than water, and offers much less resistance, allowing the animals to go faster when jumping than when swimming.

But there's efficiency, and then there's just plain showing off. (Photo by the NOAA)

A typical killer whale is about 24 feet long and weighs 6000 lbs, making them the largest member of the dolphin family. They have a distinctive white “eyepatch”, which is not actually part of their eye at all. The patch is above and behind the actual eye.

Currently there is only one recognized species of killer whales, but scientists believe that further study is likely to separate this into a number of distinct species. Some killer whales are transient, roaming the waters at will, while others are resident, staying in the same place year-round. Several resident populations may be endangered, but nothing will be officially designated until research determines how many actual distinct species of killer whale exist.

4.2b – The Dolphin

Smarter than the average bear — and smoother, too. (Photo by NASA)

The dolphin family is the largest group of cetaceans, with 37 known species. Included in the dolphin family is its largest member, the killer whale, which you may not realize is a type of dolphin. However the killer whale is unique enough that it will receive its own article.

Dolphins are remarkable, wonderful animals that we can’t even pretend to fully understand. They have the least hair of any mammal, with some species losing their hair before they are even born. They are very smooth and hydro-dynamic, able to swim quickly by moving their tails up and down.

As a predatory animal, dolphins eat a lot of fishes and small squids, and they have a variety of adaptations for hunting. For one, dolphins have strong eyesight and hearing, able to hear frequencies ten times higher than those humans can detect. Strangely enough, however, even though dolphins have ear holes, they don’t really use them for hearing. Instead, sound waves are absorbed by a pocket of fat in the animal’s lower jaw, the information transported from there to the brain. In this sense the dolphin’s “ear” is located very close to its mouth, making it easier to coordinate the two.

On top of all this, dolphins have a great sense of touch and possess echolocation to accurately pinpoint objects in the water even when they can’t be seen. They do not, however, have a sense of smell, though they may be able to taste smells with their mouth. If you breathed through a hole on top of your head, maybe you wouldn’t care to have a sense of smell either.

Dolphins live and hunt in groups of about a dozen, known as pods. Sometimes pods will combine to form super-pods, which can contain as many as a thousand dolphins, which is exactly as incredible as it sounds. Dolphins use a variety of hunting techniques, including herding fish into tight-knit balls and trapping fish between the pod and a shoreline, to make catching them easier.

The dolphins that swim together win together. (Photo by Serguei S. Dakachev)

You have probably heard that dolphins are smart, and this is true. The problem is that we don’t know exactly how intelligent they really are. There are several reasons for this uncertainty. For one thing, it’s expensive to do standardized tests on animals that require so much space and water. For another, dolphins evolved in the water and may have completely different concepts and ways of thinking than land-based animals, making it harder to judge any results we get from our expensive tests. For a third thing, their brains are completely different from ours. Dolphins not only have larger brains than humans, plus the third organ on top for echolocation, but also their two brain hemispheres are not connected in the same way ours are. They just aren’t the same as us, making it difficult to accurately judge their intelligence.

But we have evidence that they are at least as intelligent as elephants, and they may be a good deal more intelligent than that. Dolphins are capable of tool use in the wild, and are able to teach learned behaviours to one another. They are exceptional mimics, able to quickly copy each other and even other species. They are highly cooperative and social animals, and are even able to work with other species despite a lack of common language. They even work with humans in the wild. There are dolphins that have learned, completely without our prompting, to herd fish toward humans on shore. The humans cast nets on the fish, and the dolphins get to eat the fish that escape from the nets. Now that’s teamwork.

Getting back to the brain, the fact that dolphins have two distinct sides that are not well-connected leads to some curious behaviours. When a dolphin needs to sleep, it can rest only one half of the brain at a time, leaving the other half awake enough to swim slowly and watch for danger. Dolphins in captivity feel safe enough to rest both halves at the same time, but in order to keep breathing they have an automatic swim reflex that moves their tails back and forth to keep their blowhole above the surface.

That’s just the beginning of the things we don’t really understand about dolphins. They appear, remarkably enough, to have a seemingly impossible ability to heal wounds, similar to the healing factor of Wolverine, the Marvel super-hero. A dolphin can survive wounds that would kill most other animals, including gaping bites that should cause them to bleed to death. Rather than dying, the dolphin can quickly heal up the injury. Gaping wounds can heal so effectively that the body’s contour and shape are maintained. The animal will scar, but will not be permanently damaged, and we have no real idea how this works.

Conclusion: dolphins are mutant superheroes of the sea. (Photo by AllenMcC)

We don’t even truly understand how their echolocation works. Dolphins make a series of clicking noises to send sound out, and then receive the echoes that come back from surrounding objects, interpreting the information into a visual map of everything nearby. But it may be that, in addition to simply hearing the returning sound, they also absorb the sound into their teeth, which act as sonar receptors. Dolphins can have as many as 250 teeth, which is a lot of receptors. We don’t really know how it works or if we’re even right about the teeth thing. All we can really say is, “Dolphins: What the hell?”

One thing we do know is that they love to play. Dolphins will leap out of the water and perform acrobatic manoeuvres for the sheer joy of it. They play with seaweed, play-fight with one another, bully other animals for fun, and surf along waves, including the waves in front of ships. They can spontaneously play with human swimmers, and also help them when they are in distress, such as one case where dolphins chased sharks away from a stranded swimmer until help arrived.

They might even be creative, and make a sort of water-based art just because they want to. Dolphins in captivity have been observed to form a vortex in the water and blow a ring of bubbles into the middle of it, forming a swirling ring of air in the middle of the water. They then step back and use their echolocation to study the bubble, as though admiring their creation. Once they are satisfied, they will destroy the bubble by biting it.

Dolphins are found all over the world, and are one of the most interesting, beloved species we know. Unfortunately we also cause them harm through hunting, accidentally catching them in fishing nets, and polluting the ocean waters, the chemicals from which can concentrate in dolphin bodies, since they are at or near the top of many ocean food chains.

Dolphin distribution.

4.1c – The Humpback Whale

 

A whale with a song in its heart. (Photo by the NOAA)

Only about one-third to one-half the size of a blue whale, the humpback whale is nevertheless still an impressive specimen, weighing in at about 80,000 lbs.

It has a very distinctive body shape, with a thick humped back and large fins that are proportionally the biggest of any cetacean. These long fins help make the animal particularly acrobatic, which might not be a word you would expect to apply to such a massive creature. But it’s true. Humpback whales will not just come to the surface to breathe, they’ll do it in style, leaping out of the water with enough momentum to bring nearly their entire enormous bodies into the air, only to come splashing back down with tremendous force. As noted earlier, this may be a strategy to knock parasites loose or to scratch itches, or it may simply be that they find it tremendously fun. They also sometimes do this to stun fish by body-slamming a school of them, like a WWE wrestler who has taken so many steroids he now has his own postal code.

Holy crap. (Photo by JingZ)

Every humpback whale has a unique pattern on the underside of its tail flukes, which is different from the pattern on any other humpback whale. This makes it possible for humans to tell the difference between one whale and another, and in true human fashion we have taken the opportunity to give several of them names. One of the most well-known humpback whales is Humphrey, who would make a habit of swimming into San Francisco Bay and occasionally going up the Sacramento River for a little distance. In 1990 he became stuck on a mud flat and had to be dragged off with nets and both lured and chased back out into the ocean. Apparently learning his lesson, he has not returned, though he has been spotted now and then in other locations.

And believe me when I tell you that humpback whales really get around. They are migrating animals that spend the summer feeding in colder waters either in the north or around Antarctica. In the winter they make a long trip toward the equator, where they will mate, give birth, and raise young. During their time in these warmer waters the whales will not feed, living instead off their fat reserves. By the time their young are large enough to make the trip, they head back either north or south again for the summer and to fill up once more on krill and fish.

Some humpback whales will travel up to 16,000 miles per year going back and forth like this. The exception is the population of humpbacks living in the northern part of the Indian Ocean. They cannot go north because that pesky continent of Asia gets in the way, and they do not cross the equator to go south either. These whales spend all of their lives living in the warmer tropical waters.

When feeding, humpbacks use a variety of techniques, some of them quite clever. Their most famous strategy for catching fish is known as bubble-netting. Though the whales do not live in groups, a number of individuals will get together for a good bubble-net session, which requires cooperation and coordination. Finding a school of tasty fish, some of the whales swim in circles beneath the fish, unleashing bubbles of air from their held breath that rise in a circular net around the fish. The whales make the net of bubbles smaller and smaller, pulling the fish together. Meanwhile, other whales will swim beneath the fish to drive them toward the surface, and still more will patrol the edges of the net and make noises to ensure the fish stay inside the bubbles. When the fish are all nicely clumped together near the surface, the whales will make feeding runs on them, swallowing huge mouthfuls at a time.

No matter where they live, humpback whales are known for their ability to sing, and it truly is a remarkable thing. Only the males will sing, and we do not know for certain why they do it. It could be anything from a communication method among scattered whales to a mating technique to a challenge to other males.

The song is created by forcing air through the whale’s nasal cavities in certain ways to create different tones. The whale will sing for up to 20 minutes at a time, and don’t be fooled into thinking that this is just random noise. Every local population of humpback whales has its own distinctive song, and every whale within that population will sing that exact same song every time. The songs will evolve slightly over time, and once it changes it has not been recorded to return to a previous version again. The song of the humpback whales is fascinating and ethereal.

If you would like to hear a humpback whale’s song, click on the following link to be taken to a Youtube video depicting just that: http://www.youtube.com/watch?v=WabT1L-nN-E

Like the blue whale, the humpback whale was nearly hunted to extinction by the mid-1900s. Of a global population that was once around 125,000, we reduced them to a mere 5000 before hunting was finally regulated. Their numbers have recovered better than those of the blue whale. There are now 80,000 humpback whales in the oceans, and they are no longer endangered.