'Underneath'
Off-topic discussion. Wanna talk about corsets, duct tape, or physics? This is the place. Detailed discussion of any current-season TV must be whitefonted.
I didn't quite follow the article's mentions of mitochondrial DNA. Is that the discerning factor?
Mitochondrial DNA comes only from the mother, and so it remains relatively unchanged for generations, unlike nuclear DNA. The point the article is making is that if there had been a Neanderthal mother of a Neandertal/sapiens, modern humans might have her mitochondrial DNA.
I get to go to Home Depot on my lunch to get more paint. YAY?
Am I the only who took a second to process that the paint was not actually meant to be lunch?
Star Trek inspirational posters: [link]
I was going to link that. Curse my inability to keep up around here.
HA! no, paint was not lunch. paint was acheived though and supernice friend who is visiting took it home to the painters. It sounds like I will have a painted house when I get home, but because of all the moisture yesterday, they will need to do final coats and clean up tomorrow.
Lunch is free Chinese food. I love working here. I swear, there is leftover food lying around 4 out of 5 days.
Today was the semi monthly potluck for birthdays. Supposed to start at 12. Get there, find it's been postponed until 1:15 Fine, put the salad in the fridge (which should be room temp, took it out early so it would be right) come back at 1:15. various people screw around, heating food up, etc. We don't eat until 2. feh.
Oh dear god. I think I just hurt something. May not recover.
OMIDOG!!! That's frelling hysterical.
Internets, why have you failed me?
Google query composing has failed you. Even if Ralph/Sam didn't exist, now that you've put the thought out there, give the Internets two weeks to sate your dark desires.
If this is the case, how can we know for certain that they're a different species, rather than just one family of humans?
Why should sharing one or more physical traits make for the same species?
[cross-posted to Bitches]
Timelies, all. I'm afraid I skipped-&-skimmed.
Thank you all for your kind thoughts, both here and back channel. I'm back at work today, after spending 8/4-8/10 with my family. Luckily, my sister was able to come down from Michigan in time for Mom to have her whole family with her at the end. My friends and coworkers have been incredibly supportive. Amyth and some other friends drove over from the Triangle (~75 miles) to be there for me at the viewing, a third of my officemates showed up at the funeral, and I've been overwhelmed with cards and kindness.
Next Friday I'll be going up to Michigan with my dad. Mom asked for her ashes to be interred in her family's plot, so I'll be seeing Saginaw for the first time in over 20 years. Well, a small part of it, anyway.
If this is the case, how can we know for certain that they're a different species, rather than just one family of humans? I didn't quite follow the article's mentions of mitochondrial DNA. Is that the discerning factor?
As far as I know, all of the Neandertal DNA that has been isolated is mitochondrial, because it's easier to extract mitochondrial DNA from degraded materials than it is nuclear (i.e. normal) DNA. As Bon says, mitochondrial DNA doesn't mix in each generation as nuclear DNA does, so it provides a relatively stable history of the maternal line, and changes in mitochondrial DNA can serve as a kind of molecular clock. But it is a limited window on genetic variation, because nuclear DNA does most of the work.
A small number of DNA samples from Neandertals about 30,000 years ago, when they were probably sharing territory with humans, seem to be clearly different from modern humans (about 25% as different from humans as chimps are). But there was a strange thing just a few weeks ago. Someone managed to extract DNA from a 100,000 year old Neandertal. The DNA was clearly different from humans, and clearly similar to the previous Neandertal samples. But oddly, the older sample was MORE differnt from humans than the younger samples. This is not what you would expect if the two species had split prior to 100,000 years ago (the usual estimate is about 300,000) continued to evolve on their own paths. That one old DNA sample might be unrepresentative. Or there might have been mixing. Or there could be a third group mixing with the other two. Or the whole molecular clock thing could be flawed.
I agree with Cindy that the statements based on mitochondrial DNA tend to be too bold for the evidence. Her question, different species or different subtype, is hard to answer, because no one has extracted DNA from our common ancestors or from other ancient groups thought to be close enought to be in our own species (the desert is cruel to DNA). We really have no standard of how different DNA has to be to be a different species. So the opinions are stronger than the data.
