Importance ratings

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 unknown) are probably not so important. For example, the fact that no-one knows how Yardangsplugin-autotooltip__plain plugin-autotooltip_bigYardangs

Yardangs are enigmatic wind-parallel ridges found in arid environments. They often form downwind of rocks in sandy environments. They can be unusually stable structures, given their sandy / dusty composition (and the fact that the wind which forms them can also erode them). form wouldn't normally be considered as important as the fact that no-one understands what causes Diabetesplugin-autotooltip__plain plugin-autotooltip_bigDiabetes (type 1)

Type 1 Diabetes is a chronic autoimmune disease that occurs either when the pancreas does not produce enough insulin, or when the body cannot effectively use the insulin it produces. Insulin is a crucial hormone required for the body to regulate and use blood sugar..

If a page doesn't have a rating, that doesn't mean it's unimportant - but that some other articles may be more important (or, it hasn't been rated yet).

Note: As with the rest of the content, the ratings are available for editing, and may change over time.

The tables below show links to examples of articles which have been given Importance Ratings (alphabetical order)

4 Stars

Aeroplanktonplugin-autotooltip__plain plugin-autotooltip_bigAeroplankton

In the 1830s, when Charles Darwin was in the middle of the Atlantic ocean aboard HMS Beagle, he decided to collect samples of falling dust, which he sent to his colleague Christian Gottfried Ehrenberg to test for the presence of living organisms. The team were surprised to find the airborne dust was carrying over sixty types of single-celled organisms they called “infusoria” (protists)
Cell Organellesplugin-autotooltip__plain plugin-autotooltip_bigCellular organelles

Eukaryotic cells are cells which have a nucleus. Within that nucleus are various discrete structures with very specific functions that are, as a group, called 'organelles'.

In the 1970s a book by professor Lynn Margulis (titled Origin of Eukaryotic Cells)
Dark Matterplugin-autotooltip__plain plugin-autotooltip_bigDark Matter

"The nature of the dominant component of galaxies and clusters remains unknown."

Source : Measuring the dark matter equation of state (Mon. Not. R. Astron. Soc. 415, L74–L77)"

In the 1930s, astronomical observations of galaxy rotations showed that the outer regions were rotating (about the galaxy's 'centre') at the same speed, or faster, than the central regions. Subsequent calculations referring to the galaxy's mass, and thus its internal gravitational attractions, showed that i…
Proton Hoppingplugin-autotooltip__plain plugin-autotooltip_bigProton Hopping

Proton hopping - a.k.a. the Grotthuss Mechanism has been said to be "the fastest known chemical reaction". The effects of which were first noted by Theodor Grotthuss in 1805, who was investigating the decomposition of water under electrolysis.

In the process, an 'excess' proton (or its opposite, a proton-deficit) 'tunnels' through the hydrogen bond network of water molecules (or other hydrogen-bonded liquids). Leading to the formation, and simultaneous breaking, of covalent bond…
Schrodinger Equationplugin-autotooltip__plain plugin-autotooltip_bigSchrödinger equation paradox

Quote from Professor Roger Penrose speaking on BBC Radio 4 'Start the week - A Theory of Everything? 20th June 2016.

"There is a deep paradox in quantum mechanics, it's a contradiction, and it's hardly ever pointed out as a contradiction. And this contradiction is actually quite a simple one, it's that you have one procedure to describe how things evolve - the Schrödinger equation, (or 'Unitary Evolution' as it's called,) and another which is what you do when you …
Sea Level Risesplugin-autotooltip__plain plugin-autotooltip_bigSea level rises

Climate change, along with the associated ice-shelf melting, contributes to sea level rise. However, the calculations linking the temperature records with ice melt leave an unexplained 12 cm/century rise in the actual levels - as measured around the world by tide gauges (and recently by satellite radar). Put another way, the levels are rising 3 to 4 times faster than can currently be explained.
Time Awarenessplugin-autotooltip__plain plugin-autotooltip_bigTime Awareness

"Anticipating events that will happen in the future is among the most important functions the brain performs. Indeed, it has been increasingly stressed that learning and memory are prospective brain functions; that is, they are only adaptive to the extent that they help animals anticipate and prepare for the future (Dudai and Carruthers, 2005; Schacter and Addis, 2007). To anticipate when events will happen, the brain has evolved mechanisms to tell time across a wide range of te…
Universe Shapeplugin-autotooltip__plain plugin-autotooltip_bigUniverse shape and size

The 'Observable Universe' is limited by the speed of light and the length of time that it has been in existence. It's possible that the 'Observable Universe' is the real size, or, because light has a finite speed, there may be more of the universe 'outside' the limit that we have so far been able to observe.

3 Stars

Bondingplugin-autotooltip__plain plugin-autotooltip_bigChemical bonding

Chemistry textbooks normally describe three types of chemical bonds - the strong attraction between atoms, ions or molecules that enables the formation of all chemical compounds.

* The Ionic bond * The Covalent bond (see notes below)
Chaos Theoryplugin-autotooltip__plain plugin-autotooltip_bigChaos Theory

unknowable

Chaos Theory is the concept that the behaviour of some complex dynamical systems (e.g. global weather patterns) can be extremely sensitive to tiny changes in initial conditions.

Any large-scale system which has a complex set of interacting feedback and feed-forward loops can become chaotic - thus making accurate and specific long-term predictions about the system unreliable, if not impossible.
Chillsplugin-autotooltip__plain plugin-autotooltip_bigChills

Note: This item refers to the emotionally or imaginatively triggered sensation of 'Frisson' rather than shiver reactions caused by cold or fever etc.

Chills, 'goosebumps' etc can be induced in a number of ways: musical, scenic, tactile, and even taste sensations etc etc.
Core Clockplugin-autotooltip__plain plugin-autotooltip_bigCore Clock

In humans, mammals, fish, insects, and very many other organisms, the 'Core Clock' which regulates variations in body functions is set to (approximately) 24 hours. This is the so-called Circadian Rhythm. - which in many organisms, is synchronised via daylight.
Cosmic Raysplugin-autotooltip__plain plugin-autotooltip_bigCosmic rays

"Cosmic rays are typically protons or atomic nuclei of elements such as helium, carbon, or iron. The most energetic have energies more than 10 million times greater than those in the world’s most powerful atom smasher, the Large Hadron Collider.
Endophytesplugin-autotooltip__plain plugin-autotooltip_bigEndophytes

Endophytes (literally “inside plants”) were first found in 1809 by examining plant sections under the microscope. They are fungal, or bacterial, or viral inclusions in plant tissues – 'foreign' materials, found in very large numbers. They're permanent fixtures, being transmitted from generation to generation of plants either through the seeds, propagation, or by ‘infection’.
Environmental Plasticsplugin-autotooltip__plain plugin-autotooltip_bigEnvironmental plastic degradation

Of the (estimated) 300 - 400 million tonnes of plastic produced worldwide every year, only around 20% is currently recycled or incinerated. Much of the remaining 80% eventually ends up in the environment.

In the environment, plastics are degraded by weathering, UV light, abrasion, and mechanical action etc - but they are also degraded by microbes (e.g.
Life On Earthplugin-autotooltip__plain plugin-autotooltip_bigLife on Earth (timespan)

There is currently no scientific agreement as to how long ago life on Earth evolved. Estimates, based on geological evidence, vary by about 200 million years - from between 3.85 billion years ago (Ga), and 3.65 Ga..

To date, the oldest undisputed fossils appear in rocks from 3.2 Ga, but recent carbon-dating techniques applied to rocks from
Menopauseplugin-autotooltip__plain plugin-autotooltip_bigMenopause

The decline in the number viable ovarian follicles, which leads to the menopause, is well documented (see Wikipedia), but, from an evolutionary perspective the reasons for its prevalence in humans are unknown.

Only a few other mammals* are known to exhibit menopause - including orcas, short-finned pilot whales and chimpanzees.
Migraineplugin-autotooltip__plain plugin-autotooltip_bigMigraine

"Chronic migraine has a great detrimental influence on a patient’s life, with a severe impact on socioeconomic functioning and quality of life. Chronic migraine affects 1–2% of the general population, and about 8% of patients with migraine; it usually develops from episodic migraine at an annual conversion rate of about 3%."
Photoisomerizationplugin-autotooltip__plain plugin-autotooltip_bigPhotoisomerization

Photo-isomerization is the name given to the structural re-arrangement of asymmetric chemical compound molecules from one 'isomer' (e.g. 'left-handed' or 'right handed') to another, when illuminated.

The process is normally reversible, is dependent on the wavelength ('colour') of the light, and is extremely rapid, in the order of picoseconds.
Protein Structuringplugin-autotooltip__plain plugin-autotooltip_bigProtein structuring

Genes set the order that amino acids (the chemical building blocks of proteins) appear in the proteins which they code for. But, working from the gene, the form which the protein's 3-D structure will take cannot as yet be predicted. The extremely complex shapes in which the protein 'folds' has a profound effect on the properties it has within an organism.

2 Stars

Deep Carbonplugin-autotooltip__plain plugin-autotooltip_bigDeep Carbon life-forms

Ongoing research into the prevalence of life-forms (predominantly bacteria and archaea) living deep in the Earth's crust is revealing them in previously unimagined quantities. Some researchers suggest that the biological diversity of deep-carbon organisms exceeds that of those on the surface.
Oil And Coalplugin-autotooltip__plain plugin-autotooltip_bigOrigins of Oil, Gas, and Coal

"[...] it is now generally accepted, but not conclusively proven, that petroleum formation predominantly arises from the decay of organic matter in the earth. [...] alternative theories should not be dismissed until it can be conclusively established that petroleum formation is due to one particular aspect of geochemistry."
Paracetamolplugin-autotooltip__plain plugin-autotooltip_bigParacetamol

"Acetaminophen (INN Paracetamol) is one of the most widely used over-the-counter antipyretic and analgesic drugs worldwide. [...] Although discovered more than 100 years ago, and used extensively for ~ 50 years, its mode of action is still unclear
Radiotrophic Fungiplugin-autotooltip__plain plugin-autotooltip_bigRadiotrophic Fungi

Radiotrophic fungi were first discovered in 2000 as black moulds growing inside and around the damaged Chernobyl Nuclear Power Plant in Ukraine. Subsequent research at the Albert Einstein College of Medicine showed that three melanin-containing fungi,
Sonoluminescenceplugin-autotooltip__plain plugin-autotooltip_bigSonoluminescence

Sonoluminescence is the emission of very short (pico-second) pulses of light from imploding bubbles in a liquid when it's subjected to strong sound waves. It was discovered in 1934 during sonar experiments at the University of Cologne.

1 Star

Bee Colony Collapseplugin-autotooltip__plain plugin-autotooltip_bigBee Colony Collapse Disorder [ CCD ]

"Colony collapse disorder (CCD) is the phenomenon that occurs when the majority of worker bees in a colony disappear and leave behind a queen, plenty of food and a few nurse bees to care for the remaining immature bees and the queen. While such disappearances have occurred throughout the history of apiculture, and were known by various names (disappearing disease, spring dwindle, May disease, autumn collapse, and fall dwindle disease), the syndrome was rena…
Cmb Excessplugin-autotooltip__plain plugin-autotooltip_bigCosmic Microwave Background excess

"The cosmic microwave background (CMB) is currently our most precise window on the physics of the early universe. Measurements of the frequency spectrum of the CMB can rule out alternative cosmologies and place limits on physical processes that may distort the spectrum, including dark matter particle decay and reionization.
Hair Greyingplugin-autotooltip__plain plugin-autotooltip_bigHair greying (canities)

"Hair greying (referred to during ageing as ‘canities’) is one of the earliest and most visible indicators of ageing in humans. The social significance of greying persists across cultures, geographical locations, and ethnicities, alongside a now-widespread interest in its reversal.