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Content Guidelinesplugin-autotooltip__plain plugin-autotooltip_bigContent guidelines

Ideas for new topics are always welcomed, from experts and non-experts alike - if you're not sure if they'll be accepted by other editors, put them in the 'Proposed content' section for approval. The easiest way to create a new page is to use the

Registrationplugin-autotooltip__plain plugin-autotooltip_bigRegistration

At present, only registered users can create and edit articles. The registration process is very straightforward. Just click the 'Register' link at the top right of any page.

After you've registered, you'll be able to login with your password at any time…

How to edit pagesplugin-autotooltip__plain plugin-autotooltip_bigEditing pages

Once you're logged in, a grey floating 'Tool' menu at the right hand side of the screen enables access to all the main 'Content Pages' for editing. (Note: Some pages, such as the site info etc. are locked)

Like most Wikis, the site doesn't use

Importance Ratingsplugin-autotooltip__plain plugin-autotooltip_bigImportance ratings

In a departure from the usual Wiki format, Wikenigma assigns 'Importance Ratings' to some pages.

The idea is to separate articles which are considered (by the editors) to cover exceptionally important unknown issues from those which (although also u…

Faqplugin-autotooltip__plain plugin-autotooltip_bigFrequently Asked Questions

Q. Why the weird syntax? A. Like most Wikis, the site doesn't use HTML for formatting (security reasons etc). A guide to the special syntax can be found here. Unfortunately it can be quite confusing at first - but there's now a new 'Visual …

Newsplugin-autotooltip__plain plugin-autotooltip_bigNews

[ newest at the top ]

• Oct 2020 : A milestone of 500 unknown articles has been reached.

• Aug 2020 : Currently (beta) testing the new 'WYSIWYG' (What You See Is What You Get) page editor. It greatly simplifies the editing process, avoiding the need to learn th…

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Use this form to send a message to Wikenigma . . . [ * note: all fields must be completed ]

Legalplugin-autotooltip__plain plugin-autotooltip_bigLegal

Content in general

Please note that in common with other publicly editable wikis, this website is not responsible for content posted by the public. Nevertheless, the ongoing editing process should be able to remove unsuitable content in a reasonable time. If you…


538 unknowns listed

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The best way to donate is by adding new original content !

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Wikenigma - an Encyclopaedia of Unknowns Wikenigma - an Encyclopaedia of the Unknown Science

Species Extinction (mammalian)

Wikipedia maintains a list of mammalian species which are classified as possibly extinct. The list currently runs to more than 20 species which are presumed to have become extinct in the last 100 years or so.

But the verification is problematic - occasionally 'extinct' species re-appear [Ref. Needed]

If it were necessary to be absolutely certain that a loss had occurred before it could be counted, the list of modern-era extinctions would be very short indeed. This is the major reason that extinction rates are usually estimated by proxy measures, such as the one that relates annual loss of rain forest to some calculation of species richness (for an extended discussion, see May et al., 1995). The trouble is that proxy estimates are difficult to verify and can lead to rate estimates of enormous magnitude (see Brooks et al., 1997). Source:Requiem Æternam: the last five hundred years of mammalian species extinctions”. In MacPhee, Ross D. E.; Sues, Hans-Dieter (eds.). Extinctions in Near Time. Advances in Vertebrate Paleobiology.

Note: This article refers only to mammalian species, by way of example to demonstrate one of the many unknown factors encountered when trying to quantify the Number of Speciesplugin-autotooltip__plain plugin-autotooltip_bigNumber of species

"“We demonstrate that after more than six decades, estimates of global species richness have failed to converge, remain highly uncertain, and in many cases, are logically inconsistent.” Source: Authors Caley, Fisher and Mengersen writing in a 2014…


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