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comment Why does human hair grow over our eyes
Given that all ones needs to do is tie their hair behind their neck, something that early hominids were perfectly capable of doing, WISIWIG is quite right and there simple was and is no selective pressure to loose this trait. I'm afraid that, simplistic as it may sound, that is the answer. Evolution is not directed, it doesn't have an end goal, if there's no selective pressure, there's no change.
1d
comment Which of the cell types commonly found in mammals has the greatest number of mitochondria?
That's fine, just paste the URL as is and someone can edit it for you. Your answer makes a lot of sense, and I agree that it is very likely going to be muscle cells, but neither of your references support it. They just explain what mitochondria are. I would particularly like to see a reference supporting your claim about photoreceptor cells, that's an interesting point. I can't accept this since you're just giving numbers with no references.
Jun
18
comment Normal death experience
That is a very different question. It asks whether a specific cause of death is painful, citing a scientific paper that claims it is not. You are asking whether we can say that in general, death is preceded by suffering. That is really not a good question for the site as it has nothing to do with biology. There are several hundred thousand ways to die. Obviously some will be painful and some will not. I don't see what we can add to that.
Jun
18
comment Normal death experience
I'm voting to close this question as off-topic because it about philosophical musings on death and not biology.
Jun
17
comment Can all animals of the same species crossbreed?
Whether dogs (Canis familliaris or Canis lupus familliaris) and wolves (Canis lupus) are the same species is debatable. I believe the modern consensus tends towards considering them different subspecies of the same species but as far as I know, the details are not entirely clear. Remember that the line between species is blurry at best.
Jun
16
comment What is the mass of a pigeon tail feather?
@ChrisH I think (no idea really) that pigeon feathers, being relatively large (I'm thinking of entire plumes here, not tiny fluffy ones) would orient themselves pointy end down because of the extra weight of the plume. I may well be wrong though.
Jun
15
comment What is the mass of a pigeon tail feather?
@JanDvorak yes, but we only care about the orientation after it hits the atmosphere. Obviously, there will be no drag coefficient in vacuum. I am guessing that as soon as it hits the atmosphere, the drag will orient it thusly.
Jun
15
comment What is the mass of a pigeon tail feather?
Heh, nothing like the old fashioned empirical approach. I would expect the feather to orient itself with the pointy bit downwards though, it should be relatively standard.
Jun
15
comment What is the mass of a pigeon tail feather?
An African or European pigeon?
Jun
14
comment Consequence of Plants as Incomplete Protein Source
@Roland I admit I'm biased since I did my PhD on selenoproteins but it's not that rare. There are 22-25 proteins (depending on how you count them) in the human genome and some animals have many more. They are also essential, those animals that have them can't really survive without them. But yes, I know I'm being pedantic, it's just that it's my field and everyone forgets about poor Sec :)
Jun
14
comment Consequence of Plants as Incomplete Protein Source
I changed the 20 to 21 amino acids since most species also code for selenocysteine.
Jun
14
comment Are trees the only source of large amounts of oxygen?
@AliceD in terms of biomass, I'm pretty sure they represent a very small fraction when compared to photosynthesizing algae and phytoplankton as you point out in your answer. Let alone the grasses. Individual trees are big, yes, but there are not that may of them. In any case, 1) I only mentioned the plant population, not biomass and 2) only a very small part of a tree's biomass is actually photosynthesizing so biomass is not really relevant anyway.
Jun
13
comment Are trees the only source of large amounts of oxygen?
Why trees? They represent a very small part of the plant population of the planet. They just happen to be big.
Jun
13
comment How do I find the number of child terms associated with a specific GO term?
@Wolgast different ontology versions presumably. Or a completely different SQL schema. The ontology files are not static, They change quite a bit and quite often. What you need is the number found in the specific ontology file you happen to be using. Don't assume that different online versions will give you the same result.
Jun
13
comment How do I find the number of child terms associated with a specific GO term?
Does it need to be done using QuickGO? Would you be open to downloading the ontology .obo file and parsing it? Do you only want direct child terms or all descendent terms (children, grandchildren etc)?
Jun
9
comment Load specific sequences in with BioSeqIO
By the way, you might be interested in my retrieveseqs.pl script. You could use that to extract the sequence you want and then run your script on it. Alternatively, use fastaindex and fastafetch from the exonerate suite.
Jun
9
comment Load specific sequences in with BioSeqIO
This would be on topic on Stack Overflow. You can also ask on biostars.org, a site dedicated to bioinformatics.
Jun
7
comment Are there any culinary fruits that are not botanically fruits or accessory fruits?
I think this would be better suited to Seasoned Advice (though I'm not sure about that site's scope, you should check first). You're not really asking anything biological here, you're asking about misnomers that chefs might be using.
Jun
7
comment Are there any culinary fruits that are not botanically fruits or accessory fruits?
I'm voting to close this question as off-topic because it's not about biology but about what chefs consider a fruit.
Jun
6
comment Are there examples of now-living species where one is descended from the other?
Very nice breakdown, +1. One nitpick, however: the unit of "evolvedness", if such a thing could be said to exist, would not be years but generations. A bacterial species is way more "evolved" than a mammal since they've had several orders of magnitude more generations in which to evolve. While I agree that saying "X is more evolved than Y" is nonsensical, if you do choose to make such a statement, you need to think in terms of generations and not time. Time is irrelevant, it is only the number of generations that counts.