Although genetic diversity has long been believed to be extremely important to long term species survival and the ability to adapt to changing environments, the narwhal have survived for eons without great genetic diversity.(Glenn Williams- N.I.S.T. (US)

The genetic surprise of narwhal

It has been, and is, a very widely held belief that genetic diversity in a population of any creature is needed in order to deal with threats from disease and environmental change.

A new study by researchers in Denmark has found that narwhal, those unusual and interesting ceteceans of the north, actually have very little genetic diversity across all populations.

In spite of that, the species seems to be doing relatively well. Estimates are the total population is about 170,000 animals.

The researchers compared DNA from ancient narwhal to those at present and are still puzzled at how the species has survived with so little genetic diversity.

The research team also compared DNA with four other Arctic species, bowhead whale, walrus, polar bear, and beluga whales (closest relative to narwhal) and found none showed evidence of a similar lack of genetic diversity.

Researchers speculate that a previous major decline in narwhal about 600,000 years ago may have created a genetic bottleneck with an increase in population beginning about 30,000 years ago. They also suggest however that because that original species decline happened very slowly the ancient narwhal may simply have somehow managed to adapt, without substantial inbreeding, and that since the recovery began, genetic diversity simply has not had time to catch up. Nevertheless, the animals have somehow managed to survive throughout the ages with this low genetic diversity.

There has long been speculation about the tusks. They may be related to mating, but also used to whack and stun prey fish. However as only five percent of females have tusks, that is not the only feeding method. (Paul Nicklen- WWF)

An Inuit elder in Pond Inlet in the Canadian Arctic was quoted in the CBC saying they adapted by migration and following their food.

The International Union for Conservation of Nature (ICUCN) red list of threatened species in 2017 downgraded the threat to the species from “near threatened” to “least concern”.

However the narwhal only migrate within Arctic waters.

The researchers are quick to point out however that the lack of genetic diversity may still pose a significant survival hurdle given the recent warming of the Arctic including less sea ice and seemingly rapidly changing environmental conditions and ecosystems.

Additional information-sources

Categories: Environment, Internet, Science and Technology
Tags: , , ,

Do you want to report an error or a typo? Click here!

@*@ Comments

Leave a Reply

Note: By submitting your comments, you acknowledge that Radio Canada International has the right to reproduce, broadcast and publicize those comments or any part thereof in any manner whatsoever. Radio Canada International does not endorse any of the views posted. Your comments will be pre-moderated and published if they meet Netiquette guidelines.

When you express your personal opinion in an online forum, you must be as courteous as if you were speaking with someone face-to-face. Insults and personal attacks will not be tolerated. To disagree with an opinion, an idea or an event is one thing, but to show disrespect for other people is quite another. Great minds don’t always think alike—and that’s precisely what makes online dialogue so interesting and valuable.

Netiquette is the set of rules of conduct governing how you should behave when communicating via the Internet. Before you post a message to a blog or forum, it’s important to read and understand these rules. Otherwise, you may be banned from posting.

  1.’s online forums are not anonymous. Users must register, and give their full name and place of residence, which are displayed alongside each of their comments. reserves the right not to publish comments if there is any doubt as to the identity of their author.
  2. Assuming the identity of another person with intent to mislead or cause harm is a serious infraction that may result in the offender being banned.
  3.’s online forums are open to everyone, without regard to age, ethnic origin, religion, gender or sexual orientation.
  4. Comments that are defamatory, hateful, racist, xenophobic, sexist, or that disparage an ethnic origin, religious affiliation or age group will not be published.
  5. In online speak, writing in ALL CAPS is considered yelling, and may be interpreted as aggressive behaviour, which is unpleasant for the people reading. Any message containing one or more words in all caps (except for initialisms and acronyms) will be rejected, as will any message containing one or more words in bold, italic or underlined characters.
  6. Use of vulgar, obscene or objectionable language is prohibited. Forums are public places and your comments could offend some users. People who use inappropriate language will be banned.
  7. Mutual respect is essential among users. Insulting, threatening or harassing another user is prohibited. You can express your disagreement with an idea without attacking anyone.
  8. Exchanging arguments and opposing views is a key component of healthy debate, but it should not turn into a dialogue or private discussion between two users who address each other without regard for the other participants. Messages of this type will not be posted.
  9. Radio Canada International publishes contents in five languages. The language used in the forums has to be the same as the contents we publish or in one of the two official languages, English or French. The usage of other languages, with the exception of some words, is forbidden. Messages that are off-topic will not be published.
  10. Making repetitive posts disrupts the flow of discussions and will not be tolerated.
  11. Adding images or any other type of file to comments is forbidden. Including hyperlinks to other websites is allowed, as long as they comply with netiquette. Radio Canada International  is in no way responsible for the content of such sites, however.
  12. Copying and pasting text written by someone else, even if you credit the author, is unacceptable if that text makes up the majority of your comment.
  13. Posting any type of advertising or call to action, in any form, to Radio Canada International  forums is prohibited.
  14. All comments and other types of content are moderated before publication. Radio Canada International  reserves the right to refuse any comment for publication.
  15. Radio Canada International  reserves the right to close a forum at any time, without notice.
  16. Radio Canada International  reserves the right to amend this code of conduct (netiquette) at any time, without notice.
  17. By participating in its online forums, you allow Radio Canada International to publish your comments on the web for an indefinite time. This also implies that these messages will be indexed by Internet search engines.
  18. Radio Canada International has no obligation to remove your messages from the web if one day you request it. We invite you to carefully consider your comments and the consequences of their posting.

Your email address will not be published. Required fields are marked *


One comment on “The genetic surprise of narwhal
  1. Avatar M.Brown says:

    It would seem they need the icy waters of the Arctic to survive as they have for so many thousands of years. With rapid climate change altering the north, will they still survive for thousands more, or even hundreds of years more?