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March 31

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If raptor-type dinosaurs existed today...

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...would it be blatently obvious to any good evolutionary biologist that modern birds had evolved from them, or were just another branch of the raptor family? Supposing that we knew about the 'raptors before we knew about birds? Thanks. --81.76.68.217 (talk) 00:02, 31 March 2009 (UTC)[reply]

Well modern birds wouldn't have evolved from them if they existed today. They'd have both evolved from a shared species, the way humans didn't evolve from chimps. As for obviousness... it depends what you consider obvious. I think if you watch robins hunt you can see that they are basically acting like raptors (in terms of posture, manner, etc.), but is that obvious, or do I just impose it? --98.217.14.211 (talk) 00:22, 31 March 2009 (UTC)[reply]
211, I think you have a mistaken assumption that whenever a new species evolves the old one must go extinct. This is often the case, but not always. StuRat (talk) 04:35, 31 March 2009 (UTC)[reply]
I could be wrong, but I think 98's point was that it's usually a fallacy to think any current species (or old species) as the same as some old species (or older species) just because we still identify them as the same species. Even things we call living fossils like the tuatara have actually changed signicantly (i.e. evolved) since prehistoric times. It only really makes sense to talk about species in a fixed point or perhaps small time frame (and even then it's still a far from great concept). Both humans and chimpanzees evolved from a common ancestor that was neither human nor chimpanzee. Birds likely evolved from various dinosaurs but the birds that we would first identify as birds then are not the same as the birds now and if dinosaurs survived as things we would still call dinosaurs they wouldn't be the same as dinosaurs then either. It's not so much a species going extinct as a species changing/evolving. Those dinosaurs that evolved in to birds didn't go extinct, they just evolved in to birds. There may be different lines (species) that evolved but went extinct and there could have been (but wasn't) species that survived but share more 'similarities' with the prehistoric dinosaurs obviously Nil Einne (talk) 11:24, 31 March 2009 (UTC)[reply]

If biologists had access to living raptors - doubtless they could do a swift genetic study and answer the question about whether dinoaurs are birds (or birds are dinosaurs or whatever) in pretty short order. But we don't know what the answer would be because that's one experiment we can't do. SteveBaker (talk) 01:26, 31 March 2009 (UTC)[reply]

Velociraptor mongoliensis restored with large wing feathers, as evidenced by fossil quill knobs.
Greater Roadrunner
If you saw a roadrunner and velociraptor side by side, the similarity would be pretty striking. Looie496 (talk) 02:40, 31 March 2009 (UTC)[reply]
But that's a deceptive thing - which is why there is still vigorous debate on the subject. Convergent evolution could easily be the cause of that. Look at pictures of a whale and a whale-shark - they look pretty similar and they live very similar life-styles...yet they are separated by a vast chasm in evolutionary terms. SteveBaker (talk) 12:23, 31 March 2009 (UTC)[reply]
There's always been something in the movements and demeanour of European Magpies that just screams 'dinosaur!' at me. Though it's probably the case that something about the movements and demeanour of European Magpies reminds me of the guesstimated dinosaurs I've seen on TV and in the movies... ;) --Kurt Shaped Box (talk) 03:07, 31 March 2009 (UTC)[reply]
I think it's fair to say that when people today note how remarkably raptor-like birds are it's because dinosaurs-were-bird-like paleontologists like Robert T. Bakker were advisors on Jurassic Park, so they made the raptors act like birds. I imagine the CGI animators watched a lot of bird videos to come up with the raptor movements. The cultural effect is such that .211 above remarks that robins remind him of raptors in their posture and manner (!). --Sean 12:35, 31 March 2009 (UTC)[reply]
There is no doubt that's true. We've never seen raptors moving - so you can't say "I've seen birds move just like raptors." because you've never seen a raptor moving. All you can say is: "I've seen birds moving just like those CGI raptors in Jurassic park (etc) that were deliberately animated to look like birds.'"...but that's a much less impressive claim - and certainly it's a circular argument! There is an expectation that if birds and dinosaurs are closely related - then perhaps one moves like the other - so on 'science' shows on TV, you'll also see animations of raptors moving like birds because that's our current best-guess based on the unproven (but increasingly likely) hypothesis that birds are dinosaurs. You'll also see guesses about what they sounded like - guesses about what color they were and guesses about how they attacked their prey (eg individually or in packs). None of those things are known with any great confidence. SteveBaker (talk) 13:07, 31 March 2009 (UTC)[reply]
I'll bet that a million years from now Humans are animated as moving like chipmunks or something. APL (talk) 16:41, 2 April 2009 (UTC)[reply]
I think if those dinosaurs existed today (and had always been around, rather than being re-created like in Jurassic Park), we would consider them birds. Avimimus or even Velociraptor would look more like a cassowary than a cassowary looks like a robin. 128.194.103.37 (talk) 12:59, 5 April 2009 (UTC)[reply]

New York City higher education

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In the period 1851-1855 what institutions of higher education in New York City (or close proximity) were offering degrees in engineering? Many thanks to anyone who can assist. Wagnerfamily (talk) 00:23, 31 March 2009 (UTC)[reply]

If you want an authoritative answer, I wouldn't know where to find it, but it's possible that Rensselaer Polytechnic Institute was the only one. They were certainly giving engineering degrees by the 1830s. Looie496 (talk) 02:32, 31 March 2009 (UTC)[reply]
I don't know where to find the answer either, but Rensselaer certainly isn't part of it -- it's well over 100 miles north of New York. --Anonymous, 03:54 UTC, March 31, 2009.
(1) Polytechnic Institute of New York University (then known as "Brooklyn Polytech")
(2) The United States Military Academy (West Point is 50 miles north of the city).
I'm not sure whather Columbia University gave engineering degress before the Civil War.
Your window is just a bit too early for Cooper Union, City College (CCNY), Stevens or Rutgers.
B00P (talk) 06:58, 31 March 2009 (UTC)[reply]
Hmm ... on reconsideration, the answer may be "none." Brooklyn Poly's first degrees were awarded in 1871, although it had an engineering program in the period you are interested in (1855). And I'm beginning to doubt that West Point's BS degrees were in engineering, although it was part of the curiculum. Sorry about that. B00P (talk) 07:41, 31 March 2009 (UTC)[reply]

Electric car

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Let's say we have an all electric car. Could we put a small fan in the front of that car, which would turn when the wind passed it as we were driving that car. Could we then hook the fan to a small generator that could assist in the car being recharged. Thus needing to be plugged into the electrical outlet for a shorter amount of time. I'm led to believe the fan would not fully recharge the car, but why? —Preceding unsigned comment added by 76.225.133.60 (talk) 07:53, 31 March 2009 (UTC)[reply]

Indeed it will not; conservation of energy is the answer. The electric engine of this car produces a mechanical work from some chemical energy; your device would transform part of this work back as chemical energy to be used again. In the energy balance, this will only make the car less efficient, loosing more energy in form of heat. It is like using part of the energy produced by a water turbine to raise up the water again, etc. Still, your idea has a base: in order to decelerate, an electric car may use the engine as an electrical generator, converting again part of the kinetic energy into electricity, which saves energy and avoids over-heating of the brakes. --pma (talk) 09:21, 31 March 2009 (UTC)[reply]
Conservation of energy and the laws of thermodynamics say that there is no such thing as a free lunch. Depressing and inconvenient though it is - it's a fundamental law of nature. In this case, the fan would increase the 'drag factor' of the car - requiring more electrical power to push it along - and this would be to a greater extent than could be recouped from the generator attached to the fan. If you did this, the car would run down faster than if you didn't do it. SteveBaker (talk) 12:20, 31 March 2009 (UTC)[reply]
But! If it was a flying car, and you were scared your engines might fail, you could use the fan you propose as an emergency source of electricity which would generate power from your continued forward motion, allowing you to at least watch your altimeter spin. See ram air turbine. --Sean 12:26, 31 March 2009 (UTC)[reply]

You could also park it facing the wind on a windy day to let it recharge a little when you are not using it. 65.121.141.34 (talk) 13:00, 31 March 2009 (UTC)[reply]

You most certainly could. It would be called "A Windmill". But why carry that weight (and drag) around with the car when you can't benefit from it? It would be vastly more logical to leave the windmill at home and just plug into it when you need to...and while you aren't plugged into it, it could be charging up batteries or running your refrigerator? But windmills take a lot of space and they break down - so wouldn't it be better still to pay the electricity company look after the windmill for you? Perhaps they could just roll the cost of doing that into your regular electricity bill. But then, wouldn't it be still better if instead of a bunch of tiny windmills, they had a few GIGANTIC ones so they could make electricity to charge everyone's electric cars...oh...wait...they do. SteveBaker (talk) 13:44, 31 March 2009 (UTC)[reply]
You could of course add a solar panel to the roof instead where you're more likely to get some benefit in recharging. The trouble is of course many car parks are by design indoor or sheltered and the cost of installing the solar panel will almost definitely take very, very long to have any pay off. Again of course you'd be better off installing the solar panel somewhere else Nil Einne (talk) 14:36, 31 March 2009 (UTC)[reply]
But the solar panel could have non-financial benefits, as well. For those who park outside and drive very little, it may provide all the electricity they need, so no effort needs to be spent recharging. For those who drive farther, it might be nice to drive in to work with almost no charge left, park in the sunlight, and have enough of a charge after work to either drive home or at least to the nearest charging location. StuRat (talk) 14:50, 31 March 2009 (UTC)[reply]
Specifically, in order to recharge the car, the fan would have to be huge. Once you add that huge fan to the car, suddenly your car is heavier and has much more air resistance. So your car needs a stronger engine. Which means you need an even larger fan, which needs an even stronger engine to haul it around, etc, etc.
The law of conservation of energy, means that you'll always wind up with these sorts of jams. Perpetual Motion enthusiests are always sure that they're very close to "balancing" that situation, but they never are. It's impossible to balance it. APL (talk) 13:18, 31 March 2009 (UTC)[reply]

The top of a car, the hood, and the trunk would afford at least 2 or 3 square meters of solar collector, assuming the car is not one of those wierd all solar powered cars which looks like a gust of wind would blow it off the road. It would not be optimally oriented in most cases, so it would not get the theoretical maximum solar input of about 1 kilowatt per square meter, but what is the present efficiency of solar cells in converting to electricity the possible 1 or 2 kilowatts of solar energy hitting the panels? How much kw or HP does it take for a small car to cruise at 55 miles per hour (88 km/h)? It would be less than the max output of the engine in a car such as the Prius, since the engine is sized for brisk acceleration and high speed driving. I seem to recall early hybrids from the 1970's needing only 5 HP to cruise. If so a car covered with efficient solar panels could have greatly extended range. Edison (talk) 15:43, 31 March 2009 (UTC)[reply]

This article says that passenger cars, in general need about 25 horsepower to cruise at 60 mph. More aerodynamic and lighter cars or slower cruiosing, could reduce the requirement significantly, since this figure is apparently for large passenger cars in general. Edison (talk) 15:50, 31 March 2009 (UTC)[reply]
The new Priuses will have solar panels as an option [1] [2] although it's only used to power the airconditioning and radio at most it seem. The Prius of course is a large car so not the best example. Solar vehicle will have info of more interest Nil Einne (talk) 00:36, 1 April 2009 (UTC)[reply]
25Hp is 18.7 kW, so your solar panels would need to be about 1000% efficient to supply all the power the car needs. When it is sunny that is. —Preceding unsigned comment added by 65.121.141.34 (talk) 20:13, 31 March 2009 (UTC)[reply]
And that doesn't include the additional weight. But let's pick a solar-panel sales company at random here is the first one that popped up on Google: This solar panel for example - covers 0.11 sq.meters - and produces a typical peak power of less than 9 watts. So to cover the roughly 3 square meters of roof space would require 30 of them and would produce 270 watts "peak" - about 1/70th of what a horribly under-powered 25Hp car needs (my car produces 170Hp). If we imagine the car getting 8 hours of continuous sunlight per day - the solar panels would give you about an extra 5 minutes of drive time! Each panel weighs 3.3lbs - so you'd be adding 100lbs to the car...not so terrible on a bigger car - but noticable on a small, electric car. If we were looking at a typical 3,000lb car - the solar panels would add about 3% to the weight - if that added 3% of the power requirements - then the solar panels would probably reduce your range rather than increasing it. SteveBaker (talk) 01:56, 1 April 2009 (UTC)[reply]
I imagine that most of the weight of those solar panels is the structure to support them. If properly integrated with the car design, the roof, hood, and trunk would provide the needed support, thus reducing the weight requirements dramatically. But yes, just taking solar panels designed for terrestrial use and bolting them to the roof of a car is probably a most unwise decision. StuRat (talk) 02:03, 1 April 2009 (UTC)[reply]
Make Magazine recently had a one page write up on a car that was home-converted to full solar. He mentioned 20-40 miles on a full charge, but tellingly, he doesn't say how long it takes to charge.[3] APL (talk) 02:41, 1 April 2009 (UTC)[reply]
Can we then assume that it recharges overnight ? :-) StuRat (talk) 17:56, 3 April 2009 (UTC) [reply]

Alternatives Sleep

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Are there any alternatives to sleep? Things that would have the same effect as a good nights sleep but enable a person to continue on without rest? 194.80.240.66 (talk) 09:45, 31 March 2009 (UTC)[reply]

One can cope sufficiently with caffeine for a period of time, perhaps a day or two, but it's by no means a substitute for sleep as it won't keep you fully alert. Sleep is curently the only way we have of 'recharging' ourselves, and repairing our bodies. —Cyclonenim (talk · contribs · email) 12:01, 31 March 2009 (UTC)[reply]
Concur with Cyclonenim. The military in particular is often interested in this sort of things, e.g. [4] and even they at the current time are only looking at reduction rather then elimination Nil Einne (talk) 14:16, 31 March 2009 (UTC)[reply]
I've found that caffeine keeps my eyes open, but after a day leaves me in a zombie-like state which makes it quite useless. StuRat (talk) 14:39, 31 March 2009 (UTC)[reply]
Death and the afterlife according to some religions. Dmcq (talk) 15:31, 31 March 2009 (UTC)[reply]
There are no alternatives to sleep. The reason why is not positively understood -- my own preferred explanation is that there is evidence that neural connections in the brain steadily get stronger during wakefulness, and only during sleep does the brain go into a state where the connections can be normalized. Without sleep, brain activity becomes steadily more erratic, causing difficulties in concentrating, and eventually hallucinations. Looie496 (talk) 17:20, 31 March 2009 (UTC)[reply]
There is an alternative to a good nights sleep through something called Polyphasic sleep where you sleep at various times throughout the day instead of one chunk at night. These often require far less total hours of sleep. It should go without saying that you should consult a doctor before trying any of these abnormal sleep cycles. Anythingapplied (talk) 03:08, 1 April 2009 (UTC)[reply]

Buried in flies

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So which species would be first to bury us, say up to our necks, if allowed to breed uncontrollably, and how long would it take? SpinningSpark 12:27, 31 March 2009 (UTC)[reply]

Presumably whatever multiplies fastest. Bacteria says "Under optimal conditions, bacteria can grow and divide extremely rapidly, and bacterial populations can double as quickly as every 9.8 minutes.", so if you started with 1 gram, they would outweigh the Earth in only 92 generations, or around 13 hours. --Sean 12:44, 31 March 2009 (UTC)[reply]
Where did that 9.8 minutes quote come from? Dauto (talk) 14:34, 31 March 2009 (UTC)[reply]
Bacteria#Growth and reproduction. It's referenced but I didn't check. Zain Ebrahim (talk) 14:40, 31 March 2009 (UTC)[reply]
That's only true if the three-dimensionality of space or the Pauli exclusion principle are among the controls we're removing. Otherwise the population growth will soon be limited to the edge of the colony and it will grow no faster than t3 instead of et. Some quick internet "research" suggests that bacterial locomotion maxes out at 200 µm/s, which would put a lower bound of 3000 years on the time needed to blanket the earth. Larger creatures could probably beat that.
(Although the bacteria could be carried by streams and ocean currents. Still, I think we're talking hundreds or thousands of years, not hours.) -- BenRG (talk) 14:53, 31 March 2009 (UTC)[reply]
Homo sapiens is a species that will bury itself, It has already made many other species extinct. - GlowWorm. —Preceding unsigned comment added by 174.130.251.46 (talk) 14:30, 31 March 2009 (UTC)[reply]

I have frequently observed this in real life. If you have a strong stomach, see the horrifying results of this practice at, for example,this page Beware, nature is cruel and vile and this picture may upset you. --Dweller (talk) 15:54, 31 March 2009 (UTC)[reply]

Given the ability to increase uncontrollably, human beings could theoretically cover the enitre planet in as few as 200 years. Assuming every human being lived in a 1 square meter area, and the human population doubling every 50 years. The land area of Earth is appx. 148 billion square meters, and the population of Earth could 192 billion by 2310. Although algebra was never my strong suit, I could be wrong. Livewireo (talk) 21:10, 31 March 2009 (UTC)[reply]
I'm sorry - I can't shake the image of people packed together at 1 sq.meter per person reproducing at maximum possible rate. Would there be viagra involved at any point in the proceedings or would we have to resort to the flying helmet and wet celery? SteveBaker (talk) 18:05, 1 April 2009 (UTC)[reply]

VH-3D Sea King [Obamacopter] range

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President Obama is coming to London with his trusty VH-3D Sea King, the range of the Sea King is not great enough to cross the Atlantic in one push, so is it transported in a plane and flown around or does it bunny hop from ships in the Atlantic refuelling? I'm fairly certain it would be the former, but someone recently said that it is possible for a helicopter to cross the Atlantic. —Preceding unsigned comment added by MedicRoo (talkcontribs) 13:16, 31 March 2009 (UTC)[reply]

Certainly it could be in-flight refuelled and get all the way across the Atlantic that way - but it's a fairly arduous and dangerous activity and I doubt they'd do it if they didn't absolutely have to. There are actually close to 30 'presidential helicopters' in the fleet and it's quite likely that some are stationed in Europe on a permanent basis for just such an occasion. SteveBaker (talk) 13:36, 31 March 2009 (UTC)[reply]

Presidential helicopters are flown over on a cargo plane, though I am not sure if they use a C-141 or a C-5. Actually, I am not sure if the Sea King has in flight refueling capability. 65.121.141.34 (talk) 15:36, 31 March 2009 (UTC)[reply]

Seeing as how the C-141 has been retired from active service since 2004, They probably use the C-5. 65.121.141.34 (talk) 14:44, 1 April 2009 (UTC)[reply]

Valuable garbage

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What can be found in the garbage and is somehow valuable? Are old electronic components valuable, if an electronic device is put apart and sold? Can old batteries be processed and re-sold? What else?--80.58.205.37 (talk) 17:40, 31 March 2009 (UTC)[reply]

An article on Dumpster diving sounds like a good place to start. --Dr Dima (talk) 18:46, 31 March 2009 (UTC)[reply]
Do curbside items count as garbage? This can include everything from computers to furniture. ~AH1(TCU) 20:43, 31 March 2009 (UTC)[reply]
Bad art would definitely satisfy your criteria (and is the subject of today's Featured Article. --Scray (talk) 01:04, 1 April 2009 (UTC)[reply]
There is undoubtedly a vast amount of valuable material in garbage. The ENTIRE problem is in separating it out. For example - every electronic item that's been tossed aside contains significant quantities of gold - but extracting the gold from the other stuff in there is a dirty, difficult job - and it's almost impossible to do it economically. That's why careful recycling is important. If glass, aluminium, clean paper and such are cleanly separated, each is extremely valuable. SteveBaker (talk) 01:31, 1 April 2009 (UTC)[reply]
I'd say the most money is to be made from fully working items which people discard because they've gone and got "the latest model". For example, many analog TVs in perfect working order are likely to be discarded as a result of the change to digital TV. While they may not have much value in a country which has already undergone the transition, I'd expect shipping them to a country where the transition is years off could still be profitable. StuRat (talk) 01:50, 1 April 2009 (UTC)[reply]
Analog TV's still have a long life right here in the USA. Remember - they still work just fine with video games, VCR's, DVD's, cable and satellite TV. Chucking them out because they can't pick up broadcast TV is silly. If you are patient - in a year or so, all of those government-subsidized TV conversion boxes are going to be flooding the market as the TV's they are connected to fail and are replaced with new digital tellies. You'll be able to pick one up on eBay for $5. SteveBaker (talk) 02:09, 1 April 2009 (UTC)[reply]
And lots of things have analog-out as their standard. If the video isn't digital to begin with, putting it on an expensive high-dev screen is pretty pointless and a low-res or analog output doesn't get any better by enlarging it. Unless Atari has an upgraded Atari 2600 I don't know about? DMacks (talk) 02:16, 1 April 2009 (UTC)[reply]
I'm not saying that analog TVs are worthless, on the contrary I have 5 of them in my home all hooked up to converter boxes, and intend to keep them for years. However, if I know anything about how people think, many will toss out the old TV as soon as they get a new one, with no thought that the old one may still have value. You probably won't be able to sell those TVs for much, due to a glut in those countries where analog broadcasts have stopped. Thus the need to transport them to a country where the transition is years away. StuRat (talk) 13:41, 2 April 2009 (UTC)[reply]

As an earlier poster wrote, the problem of separation limits the utility of much "garbage". But also transportation and marketing costs need to be considered. A single aluminum can might be returned for 2 cents, but it you drive it to the return center using 5 cents worth of gas and use 20 minutes of time you could be working, it might not be worth it. ike9898 (talk) 13:59, 1 April 2009 (UTC)[reply]

I can't even start my car with 5 cents worth of gas. And yes, you might want to wait until you have more than just the one can, before driving to the recycle center. StuRat (talk) 13:46, 2 April 2009 (UTC)[reply]
I really just meant that at that as an example to show that cost of separation isn't the only limitation. BTW, I read about one analysis that suggested that glass recycling makes little economic or environmental sense due to high cost of transporting it and the large amounts of energy required to reprocess it. ike9898 (talk) 14:50, 2 April 2009 (UTC)[reply]
Getting back to the original question - I think most things in the garbage have some value, but for many of those things (eg broken toys), there is a significant cost associated with 'extracting' that value. ike9898 (talk) 14:57, 2 April 2009 (UTC)[reply]

Old plastic drinks bottles made from Polyethylene terephthalate (PET) currently fetch a price of around €1500-1700 (US$2000-2200) per ton for recycling into Polar fleeces and are probably (excluding metals) the easiest item that is mass produced to make a profit from. Nanonic (talk) 14:32, 2 April 2009 (UTC)[reply]

rss feed

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is there an rss feed for this page? just-emery (talk) 19:02, 31 March 2009 (UTC)[reply]

Mediawiki supports an RSS for changes to every page - for this one it is http://wiki.riteme.site/w/index.php?title=Wikipedia:Reference_desk/Science&action=history&feed=rss - to access it you go to a page's history tab and click the RSS (or Atom) link in the menu on the left. That feed has all the changes (rather than one entry for every question), so you might find it rather busy. 87.115.166.150 (talk) 20:52, 31 March 2009 (UTC)[reply]

Eating carnivorous animals

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Is eating carnivores particularly unhealthy or dangerous? I know cultures do eat animals like dogs and cats, but I've talked to a few people who say they would never eat a carnivore because carnivore meat is dangerous/unhealthy in some way. Is this true? 90.195.179.46 (talk) 20:07, 31 March 2009 (UTC)[reply]

There is perhaps a grain of truth to that. If you look at fish, the large carnivore fish like tuna are the ones that accumulate mercury. I don't recall what the term for that is, but its also why eagles were so strongly effected by DDT as well. 65.121.141.34 (talk) 20:10, 31 March 2009 (UTC)[reply]
Biomagnification. TenOfAllTrades(talk) 20:14, 31 March 2009 (UTC)[reply]
And note that not all carnivores are equivalent. Those which directly eat herbivores have far less of a biomagnification problem than those at the top of a long food chain. StuRat (talk) 01:44, 1 April 2009 (UTC)[reply]
Eating the livers of (some?) carnivores can lead to potentially fatal Hypervitaminosis A. Deor (talk) 20:40, 31 March 2009 (UTC)[reply]
I suspect that one of the main reasons that carnivore animals are eaten less is that they are inefficient. It takes a lot of corn or grass to get meat on a cow, and it takes a lot of cow meat to get meat on a bear, so better to just eat the cow. 65.121.141.34 (talk) 13:48, 1 April 2009 (UTC)[reply]
In Jared Diamond's book, Guns, Germs and Steel, he suggests that most of the animals we eat are herbivores because herbivores and much more amenable to domestication (and easier to feed). ike9898 (talk) 13:52, 1 April 2009 (UTC)[reply]
Thank you, most informative. It sounds like explicitly excluding all carnivores isn't logical; only certain carnivores (those made entirely of liver, or which eat many other carnivores]] would be the "worst" ones... 90.195.179.46 (talk) 19:38, 1 April 2009 (UTC)[reply]
The answers above seem to have overlooked trichinosis and similar diseases. Yes, eating carnivores is somewhat more unhealthy than eating herbivores. Eating omnivores has some of the same issues, which is why pork is not eaten in some cultures.--Srleffler (talk) 05:00, 2 April 2009 (UTC)[reply]

There's certainly a Biblical prohibition on this sort of thing. And I recall reading that only certain members of West Coast native American tribes were permitted to eat bear meat. I am guessing there must be some reason for this. And wasn't mad cow disease linked to cows eating the leftover bits from other cows? Vranak (talk) 17:04, 2 April 2009 (UTC)[reply]

Yes, but cows aren't normally carnivores. Farmers had the habit of grinding up downer cows (those which are sick of some unknown cause), to use them to supplement the protein in their normal cattle feed. They did take the precaution of cooking or irradiating the meat first, but neither works for Mad Cow Disease. StuRat (talk) 17:48, 3 April 2009 (UTC)[reply]
One subset of eating carnivores is cannibalism, which has special health risks as any disease the prey may have is known to also be able to infect the predator. StuRat (talk) 17:52, 3 April 2009 (UTC)[reply]
Kuru (disease) is thought to be linked to cannibalism. Grantus4504 (talk) 09:27, 4 April 2009 (UTC)[reply]

extra part

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How can a girl have two vagina and other can have three breasts? Here are the videos:[two vagina] and [three breasts]. —Preceding unsigned comment added by 74.14.119.56 (talkcontribs) 16:43, 31 March 2009

Didn't watch the videos, but see supernumerary nipple and accessory breast for possible answers to the second question. TenOfAllTrades(talk) 21:56, 31 March 2009 (UTC)[reply]
I have not watched them either, but they are likely to be sexually explicit (for those who prefer to avoid such links), and I further presume that this recent discussion is highly relevant. Yes, I'm feeling kinda presumptious, I don't like following off-wiki links, especially when found on sites with names like "uselessjunk" and "efukt". --Scray (talk) 22:51, 31 March 2009 (UTC)[reply]
We had both of these questions before - and the answer was that these are clearly nothing more than clever prosthetics. Once you attune your brain to this fact and re-watch the movies with a skeptical eye, it becomes absolutely obvious. In the 'three boobs' video - the middle boob has no 'jiggle factor' whatever - it's a solid lump of plastic of some kind. Movie special-effects with clever makeup. SteveBaker (talk) 01:27, 1 April 2009 (UTC)[reply]
Another good sign is that it's relatively easy to find the name of the actress at least in the case of the 3 breasts one, for example it's given here (NSFW). (I'm purposely not giving the name for BLP reasons.) A quick Google would easily find other pictures of an actress under that name who looks the same other then 'missing' one breast. Nil Einne (talk) 06:18, 1 April 2009 (UTC)[reply]
BTW, you made a two formatting errors in your post preventing the first link from working and also making the two and three not show for either URL. I've fixed the errors. For URLs you don't use the | as a seperator, instead just a space, like this [http://www.microsoft.com This is Microsoft]. Also you never use a double || anyway Nil Einne (talk) 14:10, 1 April 2009 (UTC)[reply]

chemistry

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When a drop of bromine is added to a solution of alkene, it loses it's orange colour. Why? —Preceding unsigned comment added by Modipam (talkcontribs) 20:44, 31 March 2009 (UTC)[reply]

What makes the orange colour? What happens chemically when a solution of an alkene is mixed with bromine?
Please do your own homework.
Welcome to Wikipedia. Your question appears to be a homework question. I apologize if this is a misinterpretation, but it is our aim here not to do people's homework for them, but to merely aid them in doing it themselves. Letting someone else do your homework does not help you learn nearly as much as doing it yourself. Please attempt to solve the problem or answer the question yourself first. If you need help with a specific part of your homework, feel free to tell us where you are stuck and ask for help. If you need help grasping the concept of a problem, by all means let us know. DMacks (talk) 21:17, 31 March 2009 (UTC)[reply]
The fastest way to find the answer to this question is to open your organic chemistry text book, and read the section on alkenes. There will be a section in that chapter on the reactions of halides with alkenes. Read that, and you will find your answer there. Also, your professor told you the answer to this question in class. So just look at your class notes the for the last few days. You could read our articles on bromine and alkene, but you would not find the answer as easily as looking in the textbook that goes with your class. This question is clearly a reading comprehension question; its sole purpose is to check that you actually read the textbook and that you actually wrote down what the teacher told you to write down in class. --Jayron32.talk.contribs 00:03, 1 April 2009 (UTC)[reply]

Cleverness

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a)Who is/was the cleverest person in the world?

b)Can we ever find the true answer to (a)?

c)Is cleverness the same thing as IQ? —Preceding unsigned comment added by 79.75.48.89 (talk) 21:28, 31 March 2009 (UTC)[reply]

Regardless of your answer to (c), "cleverness" lacks a rigorous definition such that we can rank the population monotonically (IQ also lacks this). That leaves the answer to (b) as "no" and saves worrying about (a). — Lomn 21:34, 31 March 2009 (UTC)[reply]
Wow, Lomn! That was a very clever way to respond to that question. You must have a high IQ!  ;-) --Scray (talk) 22:38, 31 March 2009 (UTC) [reply]
While IQ is the most widely used form of measurment of "intelligence" at the end of the day there is no objective way to measure it. Some people have great stores of memorized knowledge. Many people are clever and can solve puzzles quickly. Many people just learn really fast. If I'm great at math and you are great with words or with reading social situations what ranks higher?
IQ was designed to work with children (its calibrated to age, so every time you double your age you need to double you total knowledge to keep the same IQ rating). In this capacity it helps identify kids that might need special attention if they are either far above the curve or far below it. Because of all of IQ's shortcommings I would never use it for anything except as a general pointer to help with children. It doesn't apply well to adults in my opinion.
So to answer your question, there really is no way to tell who is the cleverest. How would you even start to compare people from different time periods? Personally I've always been intrieged by the Greek Scholars, like Archimedies, because they were able to make breakthroughs in so many fields. Many of them were able to, in the course of their lifetime, not only make breakthroughs in Mathematics, Astronomy, Chemestry, and Physics, but Phylosophy, Theology, and Politics as well. This is all but impossible today because we are at such a high level in things like Physics that you practically have to spend a lifetime of study to make breakthroughs.Anythingapplied (talk) 02:53, 1 April 2009 (UTC)[reply]
Or put in a more historically sensitive framework, the differences we see in all of those subfields did not yet exist. (All of those except Theology, Mathematics, and Politics would have been considered a single "Natural Philosophy" by learned people even into the 18th century). --98.217.14.211 (talk) 03:47, 1 April 2009 (UTC)[reply]

One measure could be excellence in more than one field. See Polymath. --Dweller (talk) 09:17, 1 April 2009 (UTC)[reply]

a) SteveBaker
b) No
c) No
DanielLC 16:07, 1 April 2009 (UTC)[reply]

Science types needed

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This is actually an internal wikipedia issue but I'm a bit stuck. I need some scientific input into Samar Chatterjee, I don't understand or know the field so cannot assess the articles in terms of if the guy is notable or if it's simply an advert. Originally I thought "ah-ha! the wikiproject science people" can help - but that project seems completely dead. So I thought "ah-ha! surely the science reference desk must have some suitable boffins hanging around in their white coats. Anyone got any expertise in this area? willing to take a look? --Cameron Scott (talk) 23:09, 31 March 2009 (UTC)[reply]

The relevent guideline is WP:PROF. The article needs a serious rewrite, but it looks as though he barely makes the notability cut. --Jayron32.talk.contribs 23:56, 31 March 2009 (UTC)[reply]
The easiest way to assess notability for a scientist is to search Google Scholar for his name and look at the number of citations. Doing so, I see that his "citation classic" is Chatterjee & Biswas 1971, which gets all of 6 cites. That's better than zero, but not much -- it basically means nobody has paid any attention to his work. I'm not a hawk on notability so I wouldn't be bothered to see a 1-2 paragraph article, but more than that isn't really justified. Looie496 (talk) 00:37, 1 April 2009 (UTC)[reply]
Normally, I'm an inclusionist by nature and would recommend a keep in the grounds that the person in question is borderline notable and the article is already written and appears well-sourced. HOWEVER, the original author of the article has edited absolutely nothing else in Wikipedia and appears to know a lot of personal details of the subject that are not sourced. This makes me STRONGLY suspicious that this person is either editing an article about himself - or about a close friend, relative or colleague...which is deeply, deeply disturbing and 100% contrary to Wikipedia rules. IMHO, although it pains me to say so - I think this article should be deleted unless/until User:Sushila69 comes clean about his/her relationship to Samar Chatterjee and we can assess whether we're comfortable with risk of WP:OR and Wikipedia:Autobiography. The loss of the article is really no big deal because of the borderline notability. SteveBaker (talk) 01:19, 1 April 2009 (UTC)[reply]
Okay, I've nominated him for deletion. Clarityfiend (talk) 08:17, 1 April 2009 (UTC)[reply]