Wikipedia:Reference desk/Archives/Science/2009 June 12

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June 12

Cancer in Whales

I was wondering why whales don't die early from cancer but in fact can be very long lived and as usual have found it is a question other people have asked before and actually it's called Peto's Paradox. I haven't seen any statistics on it though. Do people study of whales that are caught to determine if they have tumours?

Can you explain why would you expect them do die early from cancer? Dauto (talk) 01:26, 12 June 2009 (UTC)

This recent article from LiveScience may be relavent. ~AH1^(TCU) 01:38, 12 June 2009 (UTC)

And silly me. I was thinking with all the coal mining going on there, there was bound to be higher rates of lung cancer. OK, that was the worst joke EVER. I didn't even laugh at that.--Jayron32.talk.contribs 03:22, 12 June 2009 (UTC)

It took me a while to get it, but when I did I thought it was pretty good...Drew Smith What I've done 03:46, 12 June 2009 (UTC)

As to the why, I was reading about Bowhead Whales and how they can live over 200 years and are 50 tons in weight. If one in eight of people die of cancer then even if we ignore the extra time a cancer has to grow but each person weight bit of the whale has that chance of a malignant cancer then overall their chance of escaping it would be something like (1 - 1/8) to the power of (50*2000/200) which google calculator tells me is about 10^-29, i.e. they should all die of cancer and it's a wonder they live so long. By the way that's very interesting about chimps having a much lower rate. Dmcq (talk) 08:36, 12 June 2009 (UTC)

I guess, more properly stated, my question really is why would anybody expect the whale cancer rate per cell to be the same as a human cancer rate per cell? I don't see why it should be. In fact I think it should be expected to be a much slower rate given that a huge animal like that is necessarily going to have a much slower methabolic rate per cell. Dauto (talk) 13:10, 12 June 2009 (UTC)

Per Dauto's remark, the assumption of a uniform risk of malignant transformation per unit body weight does not bear scrutiny. Even within the human body, different tissues (and, for that matter, different cell types within those tissues) have vastly different probabilities of becoming cancers. Malignant tumours derived from fat cells (liposarcomas and their ilk) are exceedingly rare, whereas cancers of the mucosal lining of the colon and rectum (colorectal cancer) are depressingly common. While one should be cautious about carrying these assumptions across species, it is likely that all that whale blubber – accounting for up to half the mass of the bowhead whale – is resistant to malignant transformation. TenOfAllTrades(talk) 14:12, 12 June 2009 (UTC)

As to the rate per cell the whale lives far longer so that should offset its slower metabolic rate, thats why I didn't put in a factor for their longer life. Also since the cells divide many more times there's more opportunity for them to go wrong I'd have thought even in normal growth. As to the different tissues the whales have the same tissues so corresponding organs can be compared, they have colons and rectums too only far far larger. Dmcq (talk) 14:45, 12 June 2009 (UTC)

Speculation: high metabolic rate + relatively low volume of cells = high possibility that for humans, cancer is going to kill you. Whales are low rate and high volume, even if one had cancer, would it become large enough to kill it? More interesting as Dmcq points are are high rate, low-volume animals that don't have cancer problems. --98.217.14.211 (talk) 15:40, 12 June 2009 (UTC)

I don't see that the size makes much difference once a cancer has gone malignant. It'll spread and multiply and the only difference the victim's size makes is that it'll take a little bit longer to kill a bigger one.

Going backwards from whales to humans I get that if humans had an equivalent rate then death from cancer would have to be about 0.2% or less - which sounds much more reasonable and attainable by evolution than the 10^-29 chance of surviving for whales I got the other way round. It still means whales must have some very good anti-cancer protection. I would have thought also it implies any evolutionary clock for whales would run much slower than expected for smaller mammals which mightn't be too hard to check. Dmcq (talk) 17:52, 12 June 2009 (UTC)

Well, Bovines are very resistant to all kinds of cancer. Whales are much closer to cattle (both are Ferungulata) than to humans. This does not mean that they have the same defenses, but it does make it at least plausible that whales have good cancer resistance. --Stephan Schulz (talk) 22:25, 12 June 2009 (UTC)

Where did you get that cows were resistant to cancer? I didn't find statistics but a web search seemed to show that cancer in cows was quite common and it having gone malignant was a common cause for condemning meat. And it's not as though they have long lives. Dmcq (talk) 09:43, 13 June 2009 (UTC)

I got it from the Science Magazine Podcast from April 24th (first interview, on the sequencing of the cattle genome - "cattle rarely develop spontaneous cancers [...] and almost never auto-immune diseases") - about 7'47" into the program. Archive,mp3. Sorry, not much more there, and I cannot make out the name of the researcher. --Stephan Schulz (talk) 10:16, 13 June 2009 (UTC)

I couldn't find a podcast on that date but it is a veyr interesting site. Seemingly people with Down's syndrome only get half the rate of cancer and primates in general get only a tenth of the cancer of humans. The authors seem to think our cancer protection has been compromised in the interest of growing a bigger brain. The primate rate is only ten times as much as I was calculating a whale had so well within the reach of whale evolution I'd have thought considering it isn't anywhere near so important for primates. So I consider the question as probably resolved. Cancer rates can be very variable and human rates are particularly bad considering our size and lifespan. Dmcq (talk) 12:24, 13 June 2009 (UTC)

Sorry about the link - I mixed up the Science and the Nature Podcast sites (I had to check both to find the Podcast again). The Science Archive page is [feed://www.sciencemag.org/rss/podcast.xml], but Wikipedia does not render that as a clickable link. The mp3 link above should work. --Stephan Schulz (talk) 13:19, 13 June 2009 (UTC)

Thanks very much for that, another good site for me to bookmark. I'll try and follow it up. Dmcq (talk) 12:00, 15 June 2009 (UTC)

Tidally lock

Formation and evolution of the solar system#Moon-ring system said Europa, Io is tidally lock from Jupiter. is Titan tidally lock from Saturn? Does that mean Europa is moving further away from Jupiter? Is Titan moving away from Saturn? Pluto is also tidally lock with Charon. Does that mean eventually their moon will escape away from planet, until the moon escapes and become a own planet. Even the source isn't too clear.--69.226.38.106 (talk) 04:01, 12 June 2009 (UTC)

See Tidal locking. We do have an article on this... --Jayron32.talk.contribs 04:19, 12 June 2009 (UTC)

On List of known tidally locked bodies they only gave lists of planet/moon in locking. But they didn't say if moon is moving away or closer to planet. Which ratio means moon s moving closer to planet is 3:2 or 2:3?--69.226.38.106 (talk) 04:30, 12 June 2009 (UTC)

The ratios have nothing to do with the movement closer to and farther from the respective planets; the ratios have to do with the nature of the tidal lock. The ratio 3:2 means that the object makes three rotations per two orbits; 2:3 would mean two rotations per three orbits. As far as moving away from or towards the planet, you would have to know whether or not the moon's rotational speed is getting faster or slower as a result of the tidal lock. If the moon had to slow down to become locked, then, by conservation of angular momentum, it will be move FASTER in its orbit, thus drifting away from its planet. If it had to speed up its rotation, then it will have to slow down its orbit, and will drift towards its planet. This is all explained in the article. --Jayron32.talk.contribs 05:28, 12 June 2009 (UTC)

The article Tidal acceleration explains in more detail about the drifting away from a planet by a moon as the result of Tidal locking. --Jayron32.talk.contribs 05:31, 12 June 2009 (UTC)

Jayron's answer is slightly imprecise but he pointed to the article (Tidal acceleration) that explains all that in detail. To answer the OP's questions: Yes, Europa is moving away from Jupiter but not because it is tidally locked. It does so because it's orbit around Jupiter is prograde with a period longer than Jupiter's rotational period. samething is true for Titan. Triton, on the other hand has a retrograde orbit and is therefore moving closer to Neptune. Charon's orbit is stable because Pluto itself is also tidally locked. Dauto (talk) 06:01, 12 June 2009 (UTC)

Ok having read the article on this; i was thinking wouldnt the gravitational pull of the planet counter this making it more of a Elastic Orbit? it moves further away but gets pulled back in?Chromagnum (talk) 10:45, 17 June 2009 (UTC)

Question about polish people

Do Poles have yellow skin like that of a chinaman? They appear to, despite being otherwise 'white' in appearance.--Kempist (talk) 10:50, 12 June 2009 (UTC)

There's a picture of some at the start of the Poles article. I don't see what you're seeing. Perhaps you have an old picture that has gone a bit yellow? Dmcq (talk) 12:49, 12 June 2009 (UTC)

No, I saw a guy today who was obviously Polish/Slavic and he looked almost exactly the same as white British except with a yellow tone to his skin that white British people generally lack.--Kempist (talk) 13:11, 12 June 2009 (UTC)

No, I don't. In fact, people frequently remark about how tan I am, but maybe I'm the exception to the rule. A Quest For Knowledge (talk) 13:14, 12 June 2009 (UTC)

Not sure what you are referring to. Most Poles are Slavs, and so share similar characteristics to other Slavs, such as Russians or Ukranians. However, Poland is surround by nations of different ethnicities, so there is bound to be a wide variation in appearances as people intermarry. Consider that the Magyars of Hungary and the Estonians are both Uralic peoples originally from Central Asia, while the Germans likely originated on the Baltic shores of Scandanavia. The fact is there is far more variance than assumed in an "ethnic" group, and such definitions are fluid and hard to nail down. What makes Nicholas Sarkozy French and Alberto Fujimori Peruvian and Linda Ronstadt Mexican-American is not just genetic lineage, but also environment. A person is Polish because they live in Poland, even if all eight of their great grandparents came from other countries... --Jayron32.talk.contribs 13:25, 12 June 2009 (UTC)

Discussing peoples in Europe is particularly dicey because they don't seem to have stayed put for any considerable length of time. IMHO quite a few Polish people have a pasty to rosy complexion. Compare Images Voelkerwanderungkarte.png, Karte völkerwanderung.jpg, Invasions of the Roman Empire 1.png71.236.26.74 (talk) 15:42, 12 June 2009 (UTC)

I just had a look at the corresponding pictures in the British people and Poles articles. Comparing them against each other there is an overall slight difference in the shape of the heads I think but otherwise nothing at all obvious I think. Have you seen a lot of people from Poland? it doesn't sound like it if you're talking about one person, and you sure they were from Poland rather than it being obvious somehow? After all it's quite possible for individuals to have a yellower skin either from ancestry or kidney disease or a tan or there's just a great variation amongst people. Some of those British or Polish people in the pictures could be interchanged quite easily without anyone noticing I think. Dmcq (talk) 14:30, 12 June 2009 (UTC)

Troll. Tempshill (talk) 15:27, 12 June 2009 (UTC)

If you are referring to my blunder a minute ago: Nope just dusty old idiot nor knowing how to use a gallery. :-(71.236.26.74 (talk) 15:50, 12 June 2009 (UTC)

I've seen plenty of yellow looking British and I didn't think they were Chinese. Heavy drinkers. The Poles come over here and bang they are drinking around the clock (sometimes) you too would be gone yellow. Some of that yellow is natural anyway even if you were pure black. You think this is a yellow colour but you also think that the best way to pronounce Belgique is Belgi-um. If you look at those and still see yellow, go to the fourth row down, compare the elderly orient-asian man with the elderly caucasian man. There is plenty of yellow in the skin colour but it is typical. Yellow/brown/pink (white man). You are just a bit of a snob, sorry. Don't worry about it it's good for you. ~ R.T.G 15:56, 12 June 2009 (UTC)

Since nobody has yet openly stated it, the original poster should be aware of a few things:

• This sort of comparative racial ethnography is widely discredited by modern scientific analysis. (As mentioned above, mass migrations and population diffusion are so prevalent that they render the 19th-century ethnic archetypes wholly inaccurate).
• Cultural definitions are more relevant than biological distinctions. Take a look at Polish people and Chinese people. Most anthropologists do not use skin pigment as a primary indicator of cultural identity.
• The use of the term Chinaman may be construed as pejorative (offensive) in most contexts. Our article discusses the debate surrounding use of this term.
• The lumping of skin-color and a generally offensive term suggest that the question is not asked in good faith.

Our general policy is to assume good faith on your part - possibly, this original poster is not aware of the implications of such a question - and in deference to the possibility that English is not your first language, or you are unfamiliar with cultural norms, I have posted this response as such. However, racially offensive questions are not very well received. While we don't censor such questions, because we value free speech, I think this question is inappropriate and unscientific. If you have a specific scientific question about ethnic or cultural identity; or if you have a specific question about human skin pigments, you should rephrase your question. Nimur (talk) 18:00, 12 June 2009 (UTC)

That is correct; the OP is a troll, and everyone who has responded, including myself, has been successfully trolled. Tempshill (talk) 22:00, 12 June 2009 (UTC)

Out of curiousity, are there visible differences between Koreans, Chinese and Japanese? IOW, if you see an Asian person, can you tell which country they are from? For example, can you tell that Jin from Lost really is Korean? A Quest For Knowledge (talk) 18:18, 12 June 2009 (UTC)

I see nothing racially offensive about the content of the question though I know some people treat people of other races badly for no other good reason than their color. Personally I'm prejudiced in that I have liked both the Poles and Chinese I have come across, it's my negative prejudices I have to be a bit more careful about. And by the way yes I can tell Koreans Chinese and Japanese apart quite easily normally. Dmcq (talk) 18:32, 12 June 2009 (UTC)

Well, Jin's name is very Korean, that kind of gives it away. Like guessing the nationality of man named Sean O'Grady. Livewireo (talk) 19:02, 12 June 2009 (UTC)

really? I have asked this question of numerous japanese and Chinese people (and one mongolian) and they all said they could not tell the difference between Chinese and Japanese people until they heard a person speak (or only based on cues such as clothing). Don't many people depend on this fact? Spies, Korean-born-Japanese-pop-stars etc - if there are obvious visible differences, then the vast majority of people seem to be missing them. But then i am pretty sure that no English person could really identify a Pole under controlled conditions - people think they can because of subconcious social cues.YobMod 19:07, 12 June 2009 (UTC)

Well there are lots of different types of Chinese people so you get all sorts but I must admit I'm very surprised. My first language was Chinese though I'm not Chinese myself so that probably helps with seeing them as different. Dmcq (talk) 19:22, 12 June 2009 (UTC)

There's a test at [1]. I didn't do as well as I though I would and seemingly lots of nationals from those countries do worse. Dmcq (talk) 20:44, 12 June 2009 (UTC)

I've read that carotene-based tanning products are popular in parts of Europe. That can give an unusual cast to someone's skin color. APL (talk) 18:40, 12 June 2009 (UTC)

A bit late for WP:DENY but OP blocked. See talk. hydnjo (talk) 22:26, 12 June 2009 (UTC)

tennis

What is a "winner" in a tennis game?utkarsh (talk) 11:04, 12 June 2009 (UTC)

This was answered on the Miscellaneous desk. Please don't post the same question on multiple desks. AndrewWTaylor (talk) 11:20, 12 June 2009 (UTC)

Adolescent development

http://aces.nmsu.edu/pubs/_f/f-122.pdf Reading this it seems that late adolescents (17-19) are pretty much adults, they have empathy for others, have a clear identity and are able to think logically etc. So what factors still make them adolescents from a scientific point of view. 81.154.253.59 (talk) 11:43, 12 June 2009 (UTC)

From a biological point of view, you are adult since puberty. Thinking logically, having an identity or empathy are not signs that you are an adult, not matter how desirable these characteristics are.--Mr.K. (talk) 12:42, 12 June 2009 (UTC)

Psychologically, such character traits may be used to distinguish adolescents and adults (depending on which theories are believed), which is called "psychological age". Cf. "chronological age", "biological age" and "social age". Chronological age is the most simple to detirmine, as one just counts from birth, but may not always be the most useful. Biological age has useful developmental markers such as puberty, but these may not correspond to social age - is a sexually functional 12 year old an adult? The answer is always culturally dependant. A 25 year old man could have the psychologically adaptive capabilities of a child, and his adult status may depend upon situations (eg. he is adult enough for sex, but all his money is stored in a trust fund controlled by others). So the scientific answer is "it depends on which science, and why the age is needed".YobMod 13:15, 12 June 2009 (UTC)

(EC with yobmod)However, from a sociological point of view, what makes one person capable of taking on adult responsibilities varies greatly from society to society, and people will tend to act as they are expected; thus when a society expects a 14-year old to be an adult, one will often find a 16-year old having adult-like psychology. When another society places the age at 18, they will find most 16-year olds to have child-like psychology. And the biological definition of adulthood is not a bright-line. Puberty is a process, and I would venture that it is the end of puberty, and not the start, that is a better definition of full adulthood, but reasonable people may disagree on when that occurs. --Jayron32.talk.contribs 13:17, 12 June 2009 (UTC)

Jepp - i didn't go into social age, but the textbook i am getting this from distinguishes that from psychological age. Social age means taking on responsibilites associated with a certain age, whereas psychological age is detirmined by "adaptive behavioural strategies". I don't think changing the social role necessarily changes the psychological age - teenage mother's need extra support as their social age is far advanced while their pschological age is not (and to some extent is dependant on biological age).YobMod 13:29, 12 June 2009 (UTC)

(outdent)One hugely influential psych theory that differentiates between adolescenthood, young adulthood, middle adulthood etc is Erikson's stages of psychosocial development. And biological changes associated with growth continue much past puberty - chest hair growth for example may not have even started by age 19.YobMod 13:29, 12 June 2009 (UTC)

There is a lot of evidence that brain development is not complete at age 18 - particularly the areas relating to self-restraint and risk-taking. Some studies show that full maturity does not arrive until perhaps age 25:

• http://www.dartmouth.edu/~news/releases/2006/02/06.html
• http://www.washingtonpost.com/wp-dyn/articles/A52687-2005Jan31.html
• http://www.youthadvocacyproject.org/pdfs/Brain%20Annotated%20Bibliography.pdf (Loads more links in here)

But we start to get into a fuzzy argument here - after all, people even later in life (in their 40's and 50's) start to change mental recall strategies from raw memory (which begins to fade) to using intelligence/logic-based strategies (which continues to strengthen). Should we argue that "brain development" continues into your 40's and 50's and declare all 30 to 40 year olds "under age" for some activities demanding cold, hard logic? Surely not?! But it's also arguable that humans evolved in a situation where they'd mostly be dead by age 25 (average longevity in the bronze age was 18 years!) - and even in ancient Rome, Greece and medieval europe 25 was about the average life-expectancy, so if brain development is still happening at age 25 - should we not consider 18 year-olds to be the "normal adults" (with their high risk-taking and poor self-restraint being considered "normal") and the 30+ year olds to be "post-adult" and incapable of considering "normal" degrees of risk? It's just a matter of terminology in the end. What we should perhaps be asking is whether it makes sense to impose limits on 17 to 19 year-olds because of this risk-taking difference. Limiting alcohol use and access to fast, dangerous machines might make sense even if we decided they were to be called "adult" because a "normal" level of risk-taking is still too risky when the stakes are that high. SteveBaker (talk) 16:20, 12 June 2009 (UTC)

Steve, although the average life expectancy in those times was 25 years or less, this was mostly a result of the large numbers of children born who did not make it to adulthood. A lot of times, if a person got past that first part, they would often live 50+ years. 65.121.141.34 (talk) 16:33, 12 June 2009 (UTC)

As mentioned, life expectancy is a terribly misleading statistic, especially if the distribution of age at death is heavily bifurcated (as is the case when infant mortality is statistically significant). Nimur (talk) 17:31, 12 June 2009 (UTC)

Cutting Limes

Why is it when I cut limes, my hands are never sticky? Actually, when I cut limes sometimes I don't wash my hands because they smell nice afterwards? Is it the low sugar content? If so, what type of sugar? --Reticuli88 (talk) 18:59, 12 June 2009 (UTC)

See Limonene the solvent action is mentioned in Orange oil. 71.236.26.74 (talk) 20:49, 12 June 2009 (UTC)

• To answer your question, when you cut out limes, oranges or lemons your knife and your hands will never be sitcky, because it is not made of oils such as meat, chickens, or barbeques. When you wash dishes or hands with citrus fruits, watermelons, apples, or grapes all you have to do is rinse with water, but you don't have to clean it with your soap.--69.226.38.106 (talk) 22:20, 12 June 2009 (UTC)

May I ask a follow-up question, regarding the washing of fruit? It's common knowledge that one should wash, say an apple or grapefruit before eating, even though you don't necessarily eat the skin of the grapefruit - but my girlfriend has a tendency to wash an apple with washing-up liquid before eating it - a little drop on the sponge, wipe fruit, rinse fruit thoroughly. I find it awful. Is this practiced/common/uncommon/unspeakable? --Ouro (blah blah) 06:40, 13 June 2009 (UTC)

Fruit gets washed mostly to get pesticide residues and waxes (the "make the fruit look pretty on display at the store stuff"). Dishwashing liquid can contain lots of chemicals and you can't know how they might react with those you wish to get rid of. In addition those chemicals only get tested for irritating skin, not for what they do if the get ingested. In case your friend doesn't like the results she gets with plain water and a brush she might try adding a bit of baking soda. It's safe to eat (for all but a very few people with certain medical problems) and if nothing else has a slight Abrasive effect. A study (sorry can't get at it) has found that vegetable washes they advertise aren't any more effective than plain water and a brush. 71.236.26.74 (talk) 07:09, 13 June 2009 (UTC)

Thanks loads, 71.236. Cheers, Ouro (blah blah) 20:37, 13 June 2009 (UTC)

One has to wonder: if residue from dishwashing soap is harmful to ingest, what about the residue left on washed plates, bowls, and silverware and subsequently transferred to the food served on them? -- 128.104.112.114 (talk) 21:02, 13 June 2009 (UTC)

Here's a summary of the study I couldn't get at. [2] They even did study dishwashing liquid which I hadn't remembered. As you can see it didn't show any beneficial effect. They didn't study residues from it though. I think there's a study on that out there somewhere, but the one I'm thinking of might be outdated by now. Rinsing your dishes after washing is a good idea. --71.236.26.74 (talk) 21:55, 13 June 2009 (UTC)

warm "blooded" plants

In his speculations about the possibility of the most ultimate spread of life into space in Infinite in All Directions, Freeman Dyson discussed the advantages of warmbloodedness and mused on the fact that plants have never evolved this trait. What conceivable advantages for plants could such a trait have? --Halcatalyst (talk) 22:46, 12 June 2009 (UTC)

Plants have evolved other safeguards against temperature changes besides "warmbloodedness". The ability to maintain a constant temperature, aka basal metabolism is a fantastically wasteful process. You basically are eating all day just to keep your temperature up. There are certainly advantages to it, but seeing as plants evolved other systems to deal with the ups and downs of the external temperature, it doesn't seem like there was much need for them to evolve this trait, given the obvious disadvantages that come along with it. --Jayron32.talk.contribs 23:12, 12 June 2009 (UTC)

I do believe it is lotus plants that elevate their temperature above the night-time surroundings. That to me would qualify as "warm-blooded" and it does convey an evolutionary advantage. I may need a few minutes to get the links though. (Especially since the 7th game of the Stanley Cup final series starts in a half-hour) Franamax (talk) 23:24, 12 June 2009 (UTC)

Whew, just in time. It is "Thermoregulating lotus flowers", R. Seymour & P. Schultze-Motel, Nature 383, 305 (26 September 1996) doi:10.1038/383305a0 My Nature subscription only lets me access fulltext back to '97, but as I remember the content, the plant upregulates to 2-3 degrees above ambient temperature. Anthems are starting, the game is on, must go now. :) Franamax (talk) 00:08, 13 June 2009 (UTC)

Warm bloodedness makes a more active life possible. You have to eat more, but you also have the energy to find the food. Plants, however, are rooted in the earth, which seriously limits their mobility and makes such a lifestyle unlikely. Unless they uproot themselves, like the Triffids. So it would make most sense if that trait evolved first. But I don't know of any real plants that can do this. The best chance of this happening seems to me to be in the water, where plants can float around and then still get their nutrients the plant way. Once they do that, the ability to swim may become an advantage, in which case warm bloodedness starts to make sense.

But then there is the necessity for muscles, which will be needed to use this energy. One way for plants to move is by growing. But then they would have to do that at an incredible pace and most of their energy would have to go into growing (and then splitting off in several plants, I imagine, something that plants are good at). The only other way that plants can move that I can think of is the way certain carnivorous plants do it. The descriptions sounds a bit like the way muscles work (note that I'm not a biologist). And the way the signal is passed on even sounds a bit like a nervous system, which seems to me to be another necessity, for rapid response to the environment. Give these plants another million years of evolution, and who knows..... DirkvdM (talk) 07:32, 13 June 2009 (UTC)

But none of those things actually require warm-bloodedness - the vast majority of animals that do these things are cold-blooded (or no blooded). Undersea life does not seem to have the same activity levels as land-based animals anyway - presumably most fish and crustaceans do not experience the daily temperature and associated activity levels of reptiles.YobMod 07:15, 14 June 2009 (UTC)

• As I recall, Dyson thought "warmblooded" plants would have some kind of advantage in deep space. I'm trying to get at what that advantage could possibly be. --Halcatalyst (talk) 20:57, 13 June 2009 (UTC)

To make things harder, most plants have a high surface area to volume ratio compared to warm blooded animals, which means they are even less energy efficient in maintaining their heat. Contributions/65.121.141.34 (talk) 13:54, 15 June 2009 (UTC)