Wikipedia:Reference desk/Archives/Science/2013 May 18

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May 18[edit]

Strange-looking cherries[edit]

Hello all, I've been meaning to ask this for some time. Lately, when shopping at one particular small grocery in my area (Central California), I've been seeing some cherries that look like two or three berries fused together, sometimes with more than one stone. Last time I shopped there, they also had heart-shaped cherries mixed in with these. Are these new varieties, or some kind of rare genetic mutation, or maybe something else? Has anyone seen anything like this in other places? 24.23.196.85 (talk) 19:15, 18 May 2013 (UTC)[reply]

Did they actually have more than one stone? WP:OR, but it wouldn't be surprising if sellers would market larger cherries when they get them, larger usually appeals to customers. μηδείς (talk) 19:23, 18 May 2013 (UTC)[reply]
There are many, many varieties of cherries. Many of them are heart-shaped. Many of them have fused fruit. Browsing the list of early California cherries here, the ones that I think of from your description are the Early Burlat (big, dark cherries), but again, there are lots of cherries. --Mr.98 (talk) 20:10, 18 May 2013 (UTC)[reply]
I've many times seen a few "Siamese twin" cherries mixed in with a batch of ordinary ones. Presumably the ones you found have mutated in some way that makes that the norm rather than the exception. Almost all the fruit we find in stores is genetically freakish, so things like that aren't incredibly surprising. Looie496 (talk) 02:17, 19 May 2013 (UTC)[reply]

Bonobo endocrinology[edit]

Does Bonobo Chimpanzee have more oxytocin \ other "friendship hormones" compared to Common Chimpanzee? 109.64.101.74 (talk) 21:20, 18 May 2013 (UTC)[reply]

First, bonobos are no longer generally referred to as chimpanzees -- they are a different (but very closely related) species. Concerning the question, I can't spot any evidence for that, though I don't think the topic has been studied very deeply. There is apparently a difference between bonobo and chimpanzee in the form of receptors for vasopressin, another peptide that is involved in social behavior. Apparently bonobos and humans share the same form, which is different from the form in chimps. See PMID 17118932 for discussion. Looie496 (talk) 02:08, 19 May 2013 (UTC)[reply]

We've heard about beneficial bacteria, perhaps there are beneficial cancers?[edit]

Perhaps some slow growing cancers that have in some way been "bred" to be somewhat differentiated, could be beneficial? For one thing they might keep immune system things like interferon on their toes? Thanks, Rich76.218.104.120 (talk) 22:57, 18 May 2013 (UTC)[reply]

What do you mean be "bred"? Plasmic Physics (talk) 00:20, 19 May 2013 (UTC)[reply]
..And, in what relavent way are bacteria like cancer? Plasmic Physics (talk) 00:53, 19 May 2013 (UTC)[reply]


What relevant way does "in what relavent way are bacteria like cancer?" have to do with my question? I'm sure you're reasonably intelligent, but your question seems off the point, perhaps you should explain your thinking first, bto motivate me to try to give a dissertation on how bacteria are like cancer. Did I ever say they were alike? Let's see both have some carbon atoms as do pencils and diamonds. What does that have to do with anything?76.218.104.120 (talk) 01:30, 19 May 2013 (UTC)[reply]
From the question header, it appears as though you are basing your logic on the assumption that they are. I'm just trying to follow the logic you used to derive your proposition. Plasmic Physics (talk) 01:43, 19 May 2013 (UTC)[reply]
The question makes sense, but I've never heard of such a thing. Cancer is defined as tissue growth that has escaped from normal genetic control, and it's hard to see how anything that has escaped from control can be good. Looie496 (talk) 02:09, 19 May 2013 (UTC)[reply]
I could imagine it occurring paradoxically on a TV show like House where, for example, someone's hypoglycemia is masked by the diabetes he develops as a secondary effect of his pancreatic cancer. But I am making up that scenario and I have never heard of it happening. μηδείς (talk) 02:34, 19 May 2013 (UTC)[reply]
(edit conflict) Have you heard of a cursed blessing? Certain types of cancer may have positive side effects, especially brain tumours, they are known to occasionally cause savant like changes. Plasmic Physics (talk) 02:37, 19 May 2013 (UTC)[reply]

ec "No violence, gentlemen -- no violence, I beg of you! Consider the furniture!". Let's not start the flame war now, shall we. The question before us, if I understand it correctly, is the following. We and our gut flora have evolved to lead at least commensal and, in some aspects, outright mutually-beneficial existence. So, the question goes, is it possible that some slow-growing cancers have evolved to be beneficial, as well? Now, to the best of my knowledge, let me try to give a (partial) answer. First of all, we did not evolve specific cancers; rather, we evolved predisposition to specific cancers. There are directly transmittable cancers, yes, such as the one decimating the tasmanian devil populations for several years now; but none AFAIK are common among humans. (Melanoma can be transmitted from mother to fetus, though; but this is off-topic right now). Human cancers occur by two primary mechanisms: random damage to the DNA due to environmental events (exposure to carcinogens, smoking, ionizing radiation, etc.), and damage to the DNA due to viral infections. These are not hereditary. Hereditary effects determine predisposition to particular types of cancer: breast cancer in BRCA1 gene carriers, colon cancer in Ashkenazi Jews, etc.; but we do not, to the best of my knowledge, carry extra genetic instructions that would make some of our stem cells differentiate into a specifically "cancerous" (but still beneficial) cell or tissue type. That of course doesn't mean that this does not happen. To understand why, let's first look into what makes a cancerous cell different from a normal cell. Cancerous cell, you see, can divide indefinitely: each one divides to make two new ones, with largely the same DNA (except usually for some mistakes), and unless there are too many of these mistakes, the two new cells can divide again, and again, and again. In fact, HeLa cancer cell line is still dividing, in vitro, since 1950s. The "normal" tissue cells, OTOH, can't do that. Instead, they have a so-called Hayflick limit on how many times a cell can divide; typically 35-60. The mechanism is simple: each time a cell divides, a small repetitive piece called telomere at the end of the DNA strand gets lost. Lose too many, and the cell can no longer divide. Now here is the tricky bit: all of our cells have genes that code for an enzyme called telomerase. This enzyme, when active, can regrow the lost telomeres. This enzyme is indeed active in most human malignant tumors. However, this also means that it is impossible to strictly define a "slow-growing" cancer: a cell with some telomerase activity may, theoretically, divide more times (100? 1000?) before reaching its Hayflick limit. Would you call such a cell a slow-growing cancerous cell or a normal cell with delayed senescence? I think at this point the question becomes purely semantic. I hope this helps. --Dr Dima (talk) 02:37, 19 May 2013 (UTC)[reply]

Thanks, that does help. Nice to have my question taken seriously rather than being browbeaten bwith questions from knowitalls.76.218.104.120 (talk)
I fail to find the provocative post neccesetated by the definition of 'flame war'. Plasmic Physics (talk) 02:58, 19 May 2013 (UTC) [reply]
Who are you to complain about provocative posts?76.218.104.120 (talk) 05:09, 22 May 2013 (UTC)[reply]
I stopped reading once I got to that phrase, lol. μηδείς (talk) 03:08, 19 May 2013 (UTC) [reply]
Incidentally, I also stopped reading at that same point. OsmanRF34 (talk) 12:37, 19 May 2013 (UTC)[reply]
Too bad :) --Dr Dima (talk) 03:31, 19 May 2013 (UTC)[reply]
Never mind me, I am sure your comments were of benefit to your intended audience. μηδείς (talk) 03:37, 19 May 2013 (UTC)[reply]
Is this what they call small talk? Plasmic Physics (talk) 03:49, 19 May 2013 (UTC)[reply]
Can small talk be so big?OsmanRF34 (talk) 12:37, 19 May 2013 (UTC) [reply]
Funny how nobody says they're engaging in "big talk" when it's just normal conversation. -- Jack of Oz [Talk] 23:37, 19 May 2013 (UTC) [reply]
Aye, but there is such a thing as big talk, as in "He talks big!" Plasmic Physics (talk) 00:07, 20 May 2013 (UTC)[reply]

Animals are slowly growing cancers. Count Iblis (talk)

Except, of course, that that conceit is entirely false, that animals follow a developmental program, with a set adult form, some like nematodes (see Caenorhabditis elegans} even having a determinate number of cells in the adult organism, while a cancer is defined as the opposite, an undefined, unregulated mass. μηδείς (talk) 23:44, 19 May 2013 (UTC)[reply]
I see, but surely there is at least some regulation, tumors need to tell the immune system to not attack them, they need to make bloodvessels to supply them etc. etc. Count Iblis (talk) 00:01, 20 May 2013 (UTC)[reply]
They don't 'need' to do those things, they just do therefore they are. Plasmic Physics (talk) 00:07, 20 May 2013 (UTC)[reply]