While surfing through the eternity of the internet one might stumble across some abstruse information and then you may wonder if they are true or complete nonsense. One of these Google-worthy statements we can find floating through social media channels many times throughout the past decades is the following: According to many people, some of them even well-known celebrities, whale sperm makes the ocean salty – but is this really true or just one of many hoaxes floating through the internet?
Whale reproduction
Over the past decades, one could read often that whales are supposed to release something between 40 and 400 gallons of sperm during one single mating act and only about 10% of it would enter the female, but how precise is this information? Let’s have a quick fact-check!
Natural selection
Indeed, it is true that whales need to produce a lot of sperm. As females can successively mate with several males, this adaptation ensures that the males’ genes are passed on successfully. In this world of sperm competition, individuals producing more sperm may have greater chances of reproductive success.
Hence, in terms of evolution, this may be one of the reasons why bigger testicles are favored by natural selection and passed on to newer generations.
For instance, North Atlantic right whales, in comparison with other animals engaged in sperm competition, evolved disproportionate adaptations. Researchers suggest that the aquatic environment may be the main influencing factor.
Since in the ocean, males cannot restrict the female’s access to other males, and they further did not evolve behavioral mating strategies for competition like the sperm whales, they purely rely on their sperm quantity and penis length for successful mating!
Studies have further confirmed that sperm competition favors the older males of the population.
Although male right whales are able to breed at about eight years of age, fatherhood commonly occurs later, from the age of 15 upwards. Scientists found a theory to explain this phenomenon: It may be possible that the testicles continue growing in terms of size and productivity.
Moreover, often it can be observed that the same males are mating successfully every year again and thus, the gene pool of future generations is becoming more uniform. This reduction in variety is a problem particularly for small populations because disadvantageous mutations can spread easily and the species is unable to adapt to changes in the environment.
Whale testicles and sperm
Whales are huge creatures, including the biggest animal that has ever lived on Earth – the blue whale. So, one might think that their reproductive organs are huge as well! And well, if you have read my article about whale penises, you know that they have truly impressive private parts with lengths up to 15% of their body length!
However, if there was a photo on the internet showing a whale with scrotums the size of a car hanging outside, wouldn’t you remember it? You do not! That’s because, although their testicles are big, they are concealed inside the body cavity.
Normally, sperm cells cannot survive with body temperatures of about 35.5° C, as it is too hot.
Nevertheless, whales found a way to ensure viable sperm quality by owning a special circulatory cooling system around it, which brings colder blood from the extremities to the testicles – it is like an inner-body AC!
However, although the blue whale is the biggest of all animals, its testicles only weigh about 45 kg each. There is another whale species that can outcompete this easily! The right whale has the biggest balls in the animal kingdom with a weight of about a ton together and a volume of about 4.5 liters (or 1.2 US gallons)! Scientists suggested that the huge amount of sperm produced is used to flush out the competitors. Nonetheless, as data on this topic is hard to gain underwater, volumes can only be roughly estimated by dissecting stranded individuals. Nevertheless, what we definitely know is that the sky-high amount mentioned by many internet users is way too much, even for a single right whale male at his best age!
Why are our oceans salty?
Salt content of the ocean
The average salinity of the earth’s oceans remains stable at about 35 PSU (practical salinity unit). PSU is a unit based on the properties of seawater conductivity and equals more or less parts per thousand or g/kg, which means that basically, one kilogram of seawater contains about 35 g of salts.
The salts contained in ocean water are mainly dissolved sodium chloride, magnesium sulfate, potassium nitrate, sodium bicarbonate, chloride, sulfate, and nitrate as well as carbonate ions.
Where does the salt come from?
Seas are old and with this, I mean really old! Several million years ago, gases from volcanoes increased the CO2 content in Earth’s atmosphere, making it more acidic than it has been before. This process led to higher levels of dissolved minerals washed out of the lava and producing salt ions. However, these minerals did not just get dissolved from lava, but also from eroded rocks all over the continents. Rivers and rain then drained most of them into the oceans.
Although some of these processes are still ongoing, the oceans remain at a more or less constant salt concentration. How come? The reason is as simple as baffling: There is life in our oceans! All these tiny marine organisms, like bacteria, use the ions for their metabolic processes. Moreover, due to chemical reactions new minerals are formed regularly and processed by marine organisms as well.
Besides runoffs from land, hydrothermal vents on the ocean floors, underwater volcano eruptions, and salt domes have a strong impact on the salinity of our oceans.
Why are lakes not salty?
Now you might wonder why our seas are salty but the lakes are not. Good question! The answer is as simple as stunning! It is just about our human perception. Lakes actually are salty, but have a different composition of salts. They contain less sodium and chloride ions, which are responsible for the salty taste, but they still contain lots of other salts, which do not create a salty taste for us.
Furthermore, lakes are usually much smaller and the water is in constant movement, getting removed by rivers and evaporation. Additionally, the missing portion of water gets replaced regularly by freshwater rain.
However, there are some famous examples of salty lakes, like for example the Great Salt Lake in Utah (USA) and the Dead Sea in Egypt and Jordan.
So, should I drink seawater?
Hence, we learned that the myth of gallons of whale sperm is just an uneducated fantasy of some people on the internet, but definitely not true!
Yet, considering all this newly gained information – we definitely agree: please do not drink seawater, not because it contains gallons of whale sperm, but because it is salt water. The high salt content dehydrates your body as you can only produce urine, which has lower salinity than sea water and thus, you will need to urinate more water than you drank in order to get rid of the excess salt!
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