Wikipedia:Reference desk/Archives/Science/2015 June 2

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June 2

Can anyone provide me with examples of some cryptids that actually turned out to be real...

The coelacanth is the obvious example that springs to mind, but are there any other examples of animals that 'mainstream opinion' has suggested are either extinct or never existed in the first place, that were eventually located and documented? For the people who are out there now, trying to find the chupacabras, pterodactyls, bigfoots, dragons, large carnivorous cats, etc. - the sort of thing that gives them hope that they're not wasting their lives... Any ideas? --Kurt Shaped Box (talk) 00:04, 2 June 2015 (UTC)

Not exactly a cryptid, but black swan is a famous example of something everyone "knew" didn't exist. Dragons flight (talk) 00:09, 2 June 2015 (UTC)

Our article doesn't go into detail about it, but I have the notion there was some skepticism about the giant squid before it was finally photographed alive. --Trovatore (talk) 00:15, 2 June 2015 (UTC)

Yes, you're absolutely right - also the colossal squid. I clearly remember the scepticism about the old stories of their existence (when people thought that the 19th century whalers were telling tall tales about having seen them) - until a few were hauled alive from the deep in the last decade or so. --Kurt Shaped Box (talk) 00:21, 2 June 2015 (UTC)

There's a few websites dedicated to animals people thought to be myths that turned out to be real, such as here and here though I'm not sure that meets your criteria. Somewhat interesting reading about the "discovery" of the Okapi (one of the animals listed at those sites). I was trying to find a report of it being claimed a myth through older books when I found that. I would be careful about drawing any equivalence to people in say, Europe, not believing in an animal claimed to have been seen by an explorer an ocean away that in their estimate sounded fantastical, and say, a large cryptid in a highly explored part of our backyard that would defy normal expectations of climate and ability to survive by food supply in that location, that the lack of a shred of real evidence for despite the proximity and quantity of humans and degree of time and continuous exploration would make just about impossible to escape detection and study.--Fuhghettaboutit (talk) 00:38, 2 June 2015 (UTC)

Fair point. Take the Loch Ness Monster, for example. The area is populous enough that if a breeding population of plesiosaur-like animals existed (because you'd need a breeding population - I refuse to believe in magical beasts), then there would be far, far, far more sightings than there have been and are. You'd probably be able to go watch them go about their business on a daily basis. --Kurt Shaped Box (talk) 01:02, 2 June 2015 (UTC)

The most famous example I can thing of to meet Fuhghettaboutit's stipulation may be the North American Moose, the descriptions of which were doubted in Europe until Thomas Jefferson famously shipped a preserved specimen to the noted French naturalist Georges-Louis Leclerc, Comte de Buffon. --Jayron32 01:41, 2 June 2015 (UTC)

Does that count as a cryptid? Moose exist in Europe (where they're called elk). From the linked article, it seems that teh assumption was that animals in the Americas were smaller and weaker than their Old World counterparts, due to an unhealthy environment. So I don't think they were doubting the existance of Moose - just that they were inferior to European ones. Iapetus (talk) 12:27, 2 June 2015 (UTC)

Moose and elk are normally considered two species. Robert McClenon (talk) 15:58, 2 June 2015 (UTC)

Yes and no. The various large deer have been given different names depending on whether they're on the east or west of the Atlantic - no problem - but the names have also been re-used. So, the animal people in NA call "moose" is called an "elk" in Europe. The articles discuss it. Matt Deres (talk) 17:40, 2 June 2015 (UTC)

In the UK (where we don't have either one in the wild), North American ones are generally called "moose" and European ones "elk" - even the Zoological Society of London - see Whipsnade Zoo where they have "lynx, brown bears, wolves, bison, reindeer, moose and wolverine". The American ones do belong to separate sub-species to the European ones, so they are different animals. Alansplodge (talk) 22:35, 3 June 2015 (UTC)

@Alansplodge: Where the confusion really sets in is that there's a North American "elk" which is different from the American moose/European "elk" group. This is one of these cases where Somebody Just Done Gone And Fouled It Up, and now you have to learn to foul it up in the same way. Wnt (talk) 22:30, 4 June 2015 (UTC)

Yes, I have no idea what WE would call those. Alansplodge (talk) 16:54, 5 June 2015 (UTC)

Apparently you can call it a wapiti if you want to. Seems to be unambiguous. It's not a word I knew before today, though. --Trovatore (talk) 04:12, 7 June 2015 (UTC)

• The coelacanth was not a cryptid, no one was saying there was a sarcopterygian living in the Indo-Pacfic until it was discovered. On the other hand there were rumors of a hairy man in the jungle before the gorilla was discovered. Nor was the existence of the giant squid doubted until pictures were taken--dead specimens were long known, unless one wants to identify it with the kraken. Even then, live pictures proved nothing. μηδείς (talk) 01:44, 2 June 2015 (UTC)

• When I looked into this, the hunt for the coelacanth had been on for years. Local fishermen were dragging them up and eating them from time immemorial. What was needed was a whole specimen. So it was a true cryptid. I wish I had moved over my book marks from my old computer (win 98) to show you how the hunt was focused. By the time a whole specimen became available it was well beyond its sell by date. The fisherman was being compensated (by what’s her name and her husband) for not selling interesting specimens for food. They had to hunt and acquire a whole coelacanth (as required, to provide a whole 'index specimen' to gain academic recognition). So it was a true cryptid; which did not just magically appear -out of nowhere- as you suggest. Please give the discovers credit for the effort that they put into this, rather than suggesting it was a chance and serendipitous Aha moment. --Aspro (talk) 20:39, 2 June 2015 (UTC)

• Sounds familiar, now that you mention it. I think that the local fisherman knew of them as an uncommon, but largely worthless fish (because it doesn't taste too good) that occasionally showed up in their catch, but never really thought any more about them. They'd either throw them back, use them as bait or sell them cheap, maybe as animal food. Reminds me a bit of those rare poisonous birds that were discovered a few years ago. Scientists were amazed that they existed, but to the locals (who hunted a lot of jungle birds), they were just a nuisance. --Kurt Shaped Box (talk) 22:55, 2 June 2015 (UTC)

As far as I can recall, there was a lot of speculation in the 1980s about whether gigantic squid were real. Whalers had found some huge squid beaks in the bellies of large whales and some scientists had calculated that for a beak of size x, then the squid would likely be size y - but there were loads of people who said that was physucally impossible. No way that an invertebrate could grow to that size, feed itself, must be a smaller squid with a large beak, etc. Anyway, FWIW - our cryptid article suggests that the coelacanth is considered a cryptid by some definitions of the term. --Kurt Shaped Box (talk) 02:34, 2 June 2015 (UTC)

This is simply wrong, it was identified as a Coelacanth by scientists when first found but the specimen couldn't be properly preserved, and it took ten years to find another specimen. It wasn't spotted at a distance or declared to be a hoax. This is all at West Indian Ocean coelacanth. μηδείς (talk) 04:02, 7 June 2015 (UTC)

@Kurt Shaped Box: - a few examples that may be of interest. These all involve the search for an organism, but may or may not fit your criteria. Xanthopan_morgani (or something like it) was famously predicted to exist by Darwin. There was much skepticism, until the moth was found. Phytophthora_ramorum was only identified in 1995, but many people were hunting for the agent that caused Sudden Oak Death for many years up to then. Unicorn#Elasmotherium_or_rhinoceros indicates that the Elasmotherium may well have been the mythical unicorn. Manna#Identification describes how this questionable food from heaven may have just been sugary secretions of scale insects. Many people are still searching/justifying the Botanical_identity_of_soma–haoma, though this is more a case of a forgotten identity, as most people believe an actual plant was used. Fly agaric is a key candidate there, and also in the Berserker#Theories. SemanticMantis (talk) 15:55, 2 June 2015 (UTC)

See okapi, which is used as a symbol for cryptids. Robert McClenon (talk) 16:00, 2 June 2015 (UTC)

Not exactly a cryptid, but when the first (stuffed) platypuses were taken back to Europe, they were widely taken to be a crude hoax.

All microbes fit the bill. When the first people used microscopes to see them, there was considerable skepticism, until the skeptics saw them for themselves. StuRat (talk) 18:14, 2 June 2015 (UTC)

Googling cryptid gorilla (since I was pretty sure they were disputed at one time), brought me this reasonable list of confirmed cryptids. We also have a an article called List of cryptids that provides their current status, but it lists only a single "confirmed" cryptid - the okapi. That's clearly misleading, as the giant squid and a few others from my external link were pretty unambiguously outside the realm of accepted science for extended periods of time. Matt Deres (talk) 02:56, 3 June 2015 (UTC)

Characteristics of numbered BtI mosquito abatement treatments

Regarding [1] and [2], from an as-yet unanswered question above, where can I find studies of the different numbered strains of BtI treatments? Is there any evidence mosquitoes have been evolving resistance? Is there evidence that the manufacturer has altered the strains in ways that change the post-release viability of the treatments? 209.210.168.146 (talk) 00:18, 2 June 2015 (UTC)

DIY clear lens fabrication

I'm looking for an inexpensive source of non-prescription glasses as props for portrait photography. Fashion glasses with clear lens are available from the online store I shop, but the problem is that you can't try them on to judge the look and fit before you get them, and there don't seem to be too many of them to choose from. I was thinking that sunglasses and reading glasses might be sources of cheap frames with a variety of styles, but you would need to replace the lenses with zero-power clear lenses. (Using a frame without glasses is an option for some frame styles, but careful examination of the picture can reveal that the lenses are absent.)

Is there an easy way to fabricate clear replacement lenses for my purpose? I'd imagine that it wouldn't be too hard if you had access to a CNC milling machine, but I don't. Any ideas? --11:56, 2 June 2015 (UTC) — Preceding unsigned comment added by 71.185.169.184 (talk)

If you are looking at portraits or stage plays, you will likely want the lenses removed. It removes the glare that they produce. I don't do photography, but I have been a stage actor for 40 years. Every pair of stage glasses I've ever seen is just a frame with no lenses. 209.149.115.214 (talk) 12:03, 2 June 2015 (UTC)

Thanks for the suggestion. I've seen someone wearing an empty glasses frame as a fashion statement. You could tell easily that there was no lenses if you saw it in person. I've also seen what I believe to be pictures taken with empty frames. If you're observant, I think you can tell that there are no lenses. One hint is the total absence of reflection (which is not a bad thing). Another is the lack of a ground beveled edge in the (absent) lenses where you'd expect to see them. (I suspect that the shadow of the frame may also look too defined if there are no lenses, but this depends on the lighting.) These problems may be fixable digitally, but I haven't tried it. --71.185.169.184 (talk) 12:24, 2 June 2015 (UTC)

Here in the UK there are several glasses makers who allow you to select frames on their website and then they will send you pairs with plain lenses so that you can see them on your face. You then send them back and they will make your prescription to fit which ever frame you like. If you don't like any, you can select again. They will charge you for any frames that you fail to return. Are there companies like this where you live? (USA?) I know of at least one of these that will sell you plain lens glasses. --TrogWoolley (talk) 14:15, 2 June 2015 (UTC)

Trivia, aside: George Reeves initially played Clark Kent with lensless frames. By the end of the series' run, he was in his mid-40s and actually needed glasses, and you could see the light reflecting sometimes... and sometimes you could catch him squinting a bit when he was Superman, even when not concentrating for X-ray vision. ←Baseball Bugs ^{What's up, Doc?} carrots→ 15:01, 2 June 2015 (UTC)

That reminds me of a shot in The Kids in the Hall where Crusher is shown so close-up that we clearly see Mark McKinney's contacts behind the character's spectacles. —Tamfang (talk) 12:52, 3 June 2015 (UTC)

We have dollar stores here like Dollar Tree where you can buy reading glasses for $1. They come in a variety of styles and prescriptions, so you could probably find some with so little magnification that it's practically a flat lens. You could also undo the screws and remove the lenses, if that's what you prefer. One issue, though, is that they are usually only half height, as is typical for reading glasses. You can also buy full sized sunglasses there and remove the lenses, or, if only lightly tinted, maybe you could leave those in, too. StuRat (talk) 18:07, 2 June 2015 (UTC)

Conflicting Statistical evidence. (yes economics and statistics are science too)

If you look here Here HERE hErE The evidence comes from 3 main sources. The World bank, IMF, and Cia factbook. Since there are conflicting claims made by all 3 sources which one is more likely to be correct and why? Any ideas on why these 3 sources came up with diferent statistics? Bias? Propoganda?! Agent of the nine (talk) 15:49, 2 June 2015 (UTC)

The CIA, International Monetary Fund, and World Bank are all reliable sources (insofar as they are widely recognized authorities who provide information). However, they each obtain and aggregate information differently. Perhaps what you want is to read about each organization's methodology for collecting economic data. Nimur (talk) 16:10, 2 June 2015 (UTC)

First, you need to explain why those conflict with one another. The first is based on GDP-PPP. The second is based on GDP-PPP/Capita. The third is based on GDP/Capita. The last is based on the human development index. To greatly simplify, supposed that I had two countries. One produced $2000 in goods a year and the other produced $1000 in goods a year. I could say that the first produced more value of goods. Now, if the first had 2000 people living in it and the second had just 10 people living in it. I could claim that the second produced more value per capita. I am not conflicting myself. I am simply making two very different statements. 209.149.115.214 (talk) 16:45, 2 June 2015 (UTC)

To the IP user (above). I was not saying that the GDP-PPP or the GPD/capita etc contradicted each other. Look at only one of those articles say the GDP/PPP. The tables for the IMF, WB, and cia have varying claims about the GDP/ppp. Nimur gave a good answer and that's what I am trying to research nowAgent of the nine (talk) 16:52, 2 June 2015 (UTC)

From the CIA's Frequently Asked Questions page: Why are there discrepancies between The World Factbook's demographic statistics and other sources? "Although estimates and projections start with the same basic data from censuses, surveys, and registration systems, final estimates and projections can differ as a result of factors including data availability, assessment, and methods and protocols...."

If you peruse the CIA's website, they have extensive free and public information in their Intelligence library. They extensively describe how they collect and analyze data - at least, that portion of data that is not obtained by clandestine means. There is also significant explanation of historical clandestine data collection in the Center for the Study of Intelligence library, from which you can extrapolate to present times.

Nimur (talk) 17:14, 2 June 2015 (UTC)

More information: IMF's 2015 World Economic Outlook is a 150+ page book including data sources, data methodology, and additional reference for more reading. You can find additional information available at no cost on IMF's public data website.

World Bank's data website also provides "free and open" access to data. They have extensive documentation of methodology. Further, they publish World Bank Research Observer, a periodical journal "...to inform nonspecialist readers about research being undertaken within the Bank and outside the Bank in areas of economics relevant for development policy."

So, if you want to read about methodology, there are a few hundred pages to start!

Nimur (talk) 19:40, 2 June 2015 (UTC)

Bubbles

Why do air bubbles deep under water take much longer to reach the surface than air bubbles near the top? For example I watched a video of sucba divers blowing air bubbles at each other and the bubbles didn't even seem to travel upwards at all, they went horiontially — Preceding unsigned comment added by 223.84.2.237 (talk) 17:51, 2 June 2015 (UTC)

I suggest that the video was rotated, and the air bubbles really were going up. Only a strong current would make them appear to move horizontally. As for how fast they rise, I believe it's the reverse of a falling object. That is, they accelerate until they reach a terminal velocity, then stay at that speed until they hit the surface, although turbulence in the water could slow them down. StuRat (talk) 17:58, 2 June 2015 (UTC)

Here's a nice description of some basic properties of bubbles [3]. Equation (3) says that the vertical velocity is equal to the Reynold's number times the bubble's radius, divided by the kinematic viscosity of water (once we rearrange to solve for velocity). The section Viscosity#Water gives a table of how dynamic viscosity changes with temperature of water, and this [4] calculator will give you kinematic viscosity. Anyway, for a fixed radius, a bubble will usually rise more slowly in very deep water, because the temperature is usually lower in the deep. SemanticMantis (talk) 20:15, 2 June 2015 (UTC)

How does density affect that calculation? At 10 metres depth, a bubble of air will have half the volume of the same mass of air just below the surface; it will expand as it rises to lower-pressure water. — Preceding unsigned comment added by LongHairedFop (talk • contribs) 20:28, 2 June 2015 (UTC)

I'm not sure that it matters at all. The seemingly reliable source I cite above says velocity only depends on radius reynold's number and viscosity, but does not go in to great deal on the assumptions needed or the derivation of the equation. Density would be a factor if the air were enclosed in a rigid vessel, but since the radius of a bubble depends on the pressure and mass (and temperature, etc), it seems that only radius is needed. SemanticMantis (talk) 16:08, 3 June 2015 (UTC)

If the deep bubble is eight times as deep as the shallow one it will have half the radius and 1/8 the volume (roughly) and so its net buoyancy is 1/8 as much. Stokes Law says the drag is proportional to R*V, so if R is halved, and F is 1/8, then V is 1/4 for the deeper bubble. Greglocock (talk) 23:09, 2 June 2015 (UTC)