Whales are the most majestic of all living reatures. Their power and sheer size, the distances they can travel, and their ability to communicate with each other over hundreds of miles, fill us with awe. But the most impressive of all is the Sperm Whale. The male Sperm Whale is the largest hunter ever known. It can grow up to 20 metres (65 feet) long, and weigh 50 tons. It also has the biggest brain (six times the size of ours), and can make the loudest noise of any liv­ing creature (it makes clicking noises rated at 230 decibels at 1 metre – louder than a rifle shot). This particular whale finds its food at the bottom of the ocean, around 2000 metres (over a mile) below the surface, in regions of darkness and extreme pressure that humans can only explore by remote controlled submarines. It lives on giant squid. These huge octopus-like creatures have long tentacles, with suckers as big as dinner plates, as evidenced by the wounds found on the sides of sperm whales that have survived battles with their mighty prey. A sperm whale needs to consume at least a ton of squid every day.

How can the sperm whale go down to such enormous depths? And how can it find its prey in utter darkness? A human diver with an air supply can only reach 300 metres before his lungs col­lapse. Even then he has to spend many hours in a decompression chamber before he can return to the surface, otherwise he dies from the compressed nitrogen in his blood bubbling into his tissues. But sperm whales go down to at least 2000 metres (they have been found at these depths after tangling in telegraph cables on the ocean floor), and they make the trip several times a day.

Let’s follow a female sperm whale as she finds her breakfast. Before she sets off, the whale spends ten minutes filling her tissues with oxygen by suck­ing in air through the blowhole on top of her head, five times a minute. In front of her skull, where our nose would be, she has a huge rounded bag filled with three tons of a milky wax-like substance called spermaceti oil (hence the name Sperm Whale). Around this bag and under the skin next to the cold water is a thick complex of blood vessels. By diverting blood to this network, the blood in this area is cooled. This cool blood then passes through the spermaceti oil, which in turn is cooled. It so­lidifies and becomes denser. This means that the whale as a whole begins to sink. It loops under the water, head first, and swims straight downwards for quarter of an hour at a steady three and a half miles (6 km) an hour. The pressure surrounding the whale is now 100 atmospheres (1400 pounds per square inch). At this depth our lungs would be crushed to a pulp. The whale’s, however, are used to this, and her rib cage collapses without harm. She just holds her breath, and shuts off blood from the extremi­ties of the body to save oxygen. The temperature is 2 degrees Celsius, and no light penetrates from the surface. It is completely dark.

To find her way around, our whale switches on her sound-locating system. This operates on the same principles as the radar used for landing aeroplanes at night, or the sonar in a submerged submarine. She sends out a pulse of high frequency clicks from a resilient set of vibrating ‘lips’ located part way down the windpipe. These sound bursts pass out through the rounded bag of oil above her upper jaw, which focuses them into an intense beam of sound, just as the rounded lens on a lighthouse lantern shapes a pencil of light that flashes across the sea. When this pencil of sound hits a solid ob­ject, the echo returns in a fraction of a second, and is picked up by a special oil-filled tube that faces forward at the tip of the lower jaw. The returning echoes pass through the oil, and stimulate nerve endings in the middle ear that build up a picture in the whale’s brain, just as our brain translates the signals from the nerves in the retina of our eye. It is likely that as she swings her head, she builds up a three dimensional picture of her surroundings, including moving objects like squid. We know that as she nears her prey the clicks increase in frequency until they merge into a buzz. We also know from ex­periments that dolphins, which have a similar echo­location system, can swim at high speed through a mesh of wires not much wider than their bodies, and distinguish between a coin and a plastic disc of the same size. Her lower jaw hinges down with a three metre bite to scoop up a squid. The giant squid including its tentacles can be as long as the whale herself, but smaller squid are also taken. The sperm whale eats three percent of her body weight in squid every day. The numbers taken are enormous. The horny beaks from fifteen thousand have been found in the stomach of one whale.

After half an hour or so, the whale needs to re­turn to the surface to breathe. Pumping warm blood through the bag of spermaceti oil, she heats it up, and it turns from solid to liquid, lowering her den­sity so that she tends to float upwards. Swimming steadily upwards, she breaks the surface and ‘sounds’, that is, she puffs a great plume of steamy air out of her nostrils, and begins to breathe in and out every 12 seconds to eliminate carbon dioxide from her blood. After a rest, she returns to the bottom for more squid.

Spermaceti oil

It is time for some questions. The most obvious difference between other whales and the Sperm Whale is the enormous, bulbous bag of spermaceti oil in its head, which makes up a quarter of the entire length of the animal. The Sperm Whale is the only whale which can forage for its prey at the bottom of the ocean. It is the only one with spermaceti oil. There is obviously a connection. For over a century these huge, harmless, intelligent beasts were slaughtered in thousands to obtain the oil to burn in lamps, and for processing into wax for candles and polishes and cosmetic creams. Why does the whale need such a lot of it? What is so different about it? The answer lies in the unusual properties of this remarkable substance. Spermaceti oil has the property of changing from a liquid to a solid just below the normal body temperature of the Sperm Whale, at 32 degrees Celsius. As it solidifies it becomes denser, that is to say, the same volume of material becomes heavier. Because there is such a large quantity of the oil, this makes a big difference to the overall density of the whale. So, by precisely controlling the temperature of the oil, either pumping blood through the oil to warm it up, or pumping it around the oil and close to the sea water above the skin to cool it, the whale can position herself in the water without effort at any depth she chooses. She can achieve neutral buoyancy over a huge range of depths.

The question is, how did the Sperm Whale evolve this amazing oil, which changes state pre­cisely around its body temperature? It is not found anywhere else in nature. Did one cell in the head of an ancestral whale mutate one day and begin to secrete oil? What use would it be, alone? Only when there are huge quantities can the oil change the overall density of such a large animal. And how was the formula for the oil tuned, so that it would change state at just the right temperature? Were there millions of failed attempts before the perfect oil came along? And the oil, alone, is no use without the blood-pumping control system to change its temperature. At body temperature it remains an oil, and has no useful effect on buoyancy.

A human brain might invent this novel ap­proach to depth control, and research the ideal liquid for the purpose, with trial and error and millions of dollars of cost. But surely such a bril­liant solution to the problem could not have come about by chance mutations? Evolution cannot set a specific goal and work towards it. Only an intel­ligent Designer can do that.

Footnote

Reproduced by kind permission of the Christadelphian Auxiliary Lecturing Society (CALS)