In 1990, a scientist named Heide-Jorgensen stumbled upon a strange whale skull in an Inuit hunter's tool shed in Greenland.
It was learned from the hunter that the animal bone was the one he had hunted in a normal whaling operation a few years earlier, and that two other similar animals had been killed during the hunt.
They have gray skin, beluga-like flippers, and a narwhal-like tail. But they do not fit the characteristics of neither narwhals nor beluga whales.
A closer look at the strange bone revealed that the animal's teeth were very peculiar. Beluga whales have 40 teeth to bite fish, while narwhals have almost no teeth (that "horn" is actually teeth), but instead feed by suction.
However, this mysterious bone has only 18 teeth, and all grow on the front of the mouth, many of which have strange spiral shapes, like the tusks (horns) of a narwhal.
At the time, Jorgensen speculated that the species might not be new, but that it was a mixed descendant of beluga whales and narwhals.
Pictured: a-narwhal, b-narluga, c-beluga whale
A hybrid of beluga and narwhals – narluga
Nearly 30 years later (2019), Jorgensen analyzed the bone's DNA and finally proved that the skull belonged to a hybrid of narwhals and beluga whales, and named it Narluga.
In dna information, he learned that the animal's mother was a narwhal and his father was a beluga whale.
The tusks of narwhals, which usually appear only on males, are considered secondary sexual characteristics, are used for courtship and display, without which it is difficult to court successfully, while male beluga whales do not have this tusks to court females.
Since both animals hide in dense sea ice for most of the year, it is difficult to observe and knowledge of them is limited.
So, scientists don't yet know how a male beluga whale can attract another female narwhal who loves tusks, but it certainly did.
From a purely scientific point of view, the two whales are about the same size and have the same number of chromosomes, and it is not a problem to mate with each other and produce offspring.
Not only between whales and whales
As strange as narluga may seem, it's just one example of a long list of known mating between different species of cetaceans, whales and whales, whales and dolphins, dolphins and dolphin stories that go far beyond that.
A 2016 study found nearly 20 such hybrids, of which only 7 occurred in captive rearing environments. The most famous of these is the hybrid kekaimalu (the name of this artificial cetacean) that was mated in 1985 by bottlenose dolphins and pseudo-killer whales.
Bottlenose dolphins seem to be particularly open. There have been numerous reports of its breeding with Guiana dolphins, coarse-toothed dolphins, grey dolphins, Pacific white-edged dolphins, long-beaked common dolphins, Atlantic spotted dolphins, Indo-Pacific bottlenose dolphins, and shortfin pilot whales and pseudo-killer whales.
Pictured: Kekaimalu
Among them, the kekaimalu just mentioned is also a fertile offspring, and in 2005 it gave birth to a healthy female "cetacean".
In addition, the study also found that most examples of cetacean hybridization are not hybridization between inbreed species. Of the 18 hybrids, only 4 belong to the so-called sister species (species that have only recently separated from each other), narwhals and beluga whales are one of them, while only two belong to the same genus, and the others are distant ones.
In general, compared with land mammals, the probability of natural hybridization of cetaceans is very high, and it may be that we usually see mestizos, but they are not identified.
Why is that?
This behavior of cetaceans is indeed very strange, most cetaceans are endangered species, and scientists can study very few samples, so it is not yet possible to explain why whales and dolphins are so flexible when mating.
However, there is a theory that this is a side effect of "social games".
From an early age, all animals will constantly try out skills that they will use later, such as hunting, and the very young kitten will start playing with dead mice to prepare it for catching mice later.
The same is true for mating, they will also choose a low-risk version, such as looking for same-sex members to test the water, of course, sometimes increase the difficulty, find different species to try.
Males who try this test may gain experience that helps them successfully mate with their peers later in life. In other words, if nothing bad happens (such as an injury or death) and there is a chance that something will be rewarded, then natural selection may encourage the attempt.
Pictured: Cetacean (left), mother whale (right)
Are cetaceans a new species?
Speaking of which, there is still a question that has not been solved, since cetaceans are so common, can cetaceans be called new species?
The simple answer is: No.
To be a species, these merger events must occur over a long period of time, and the offspring must be fertile and more willing to reproduce with each other.
Cetaceans crossed to produce fertile offspring, and these cetaceans show little tendency to reproduce with each other, perhaps because there are so few of them.
In fact, narluga has become very "personal", not only growing into adulthood, but also from the carbon characteristics of its teeth, it knows that its eating habits are more like walruses than narwhals or beluga whales.
In other words, most of narluga's food comes from the bottom of the sea, possibly clams and other invertebrates, while its mother feeds on fish on the surface of the sea.
However, scientists do not know whether narluga is fertile, and even if beluga whales and narwhals have the same chromosomes, they may not necessarily produce fertile offspring, because there are many determinants.
If a species of cetacean is abundant enough and then has its own unique eating habits, it is only a matter of time before a new species is produced.
Pictured: Lion Tiger Beast
At last
There are many new animals produced by artificial hybridization on land, such as hybrid zebras (common horses and descendants of zebras), lions and tigers, grizzly polar bears and so on.
But these are often the product of artificial intervention, and marine mammals rarely need human intervention, which is really amazing.