very true, i have two brothers and we were all very close when we were younger
ps woot for first comment lol
2005-05-16 10:17 am (UTC)
that seems to make sense. i mean youre coming from the same womb, all inside the same body, etc.
does this apply to half siblings though?
I don't know. That would be interesting.. probably more likely if they had the same mother, then if they had the same father, because of what you said about the womb, don't you think?
well when you think about it... you'll probably trust someone closer to your age then your own parent... especially when it comes to things you don't want them to know about... and blah blah blah
the subject made me chuckle =P
2005-05-16 10:29 am (UTC)
what if they are different age groups. say, fifteen years apart or more.
That makes complete sense. Each parent comes from a separate genetic line but their children blend those two together.
Imagine mom having A and B in her and dad having C and D. While you could have any mixture of A, B, C, and D either parent will still have only A and B or C and D. Your sibling will also have a mixture of A, B, C, and D, therefore being closer in structure to you.
Can you tell I was a science nerd for a long time?
Okay, if that's the case, would a half sibling be closer than their parent biologically speaking?
but i hate my sister she cause me a lots of pain
Aww, but that has nothing to do with your biological makeup.
what i always wondered if two twin boys...married two twin sisters (identical couples)
would the kids of these two families look identical or near??
genetics are neat my brother and i look like twins and we're three years apart...as do my dad and uncle
Oooh. A very good question. I wonder? I imagine it's been done for scientific experimentation, don't you think?
yeah i know a girl who always calls her brother hott. i'd be like, which brother? she goes, the hott one. shed just talk about how hott we was all the time
I am an only child, but I do have a half-sister floating around the world somewhere. Once I made eye contact with this one girl I found absolutely beautiful, It was weird, it seemed like she could have been my sister.
My sister's an alright kid, so I suppose I can live with that.
The title of this entry made me laugh, haha.
Also, why the hell does everyone get so excited about being the first one to comment on your journal?...
LOL. I guess it's the same reason people do it to the main Livejournal Announcements too.. it's just a "Hey, look at me!" thing.. kinda like a game. I think I'll post who has the most first comments each month...
2005-05-23 04:09 pm (UTC)
Funny, but not exactly
(warning, this turned out longer than I'd intended)
Unless you mean sisters who are bees, this isn't necessarily true.
For humans (or any other organism that has two sets of chromosomes):
Sister 1 is 50% genetically related to mom and 50% genetically related to dad, because that's where she got her chromosomes.
Sister 2 is also 50% related to mom and 50% related to dad, but not necessarily the same 50% as her sister is. If Dad gave Sister 1 a sperm cell with the exact complement of his DNA of that which he gave two sister 2 (possible but very, very unlikely), then even though Sisters 1 and 2 have the same father, they are not related from a paternal point of view. Ditto for Mom.
Likewise, Sisters 1 and 2 could have gotten the exact same complement of DNA from Dad (equally unlikely as the exact complement), at which point they are genetically identical from a paternal point of view.
Bottom line: sisters (or brothers) share anywhere from 0-100% of paternal DNA in common (50% is most likely), and anywhere from 0-100% maternal DNA in common (50% most likely). So, on average, siblings are 50% genetically similar, just like a child is 50% genetically similar to each given parent.
With bees, it gets really weird. Females have two sets of chromosomes (like humans), but males only have one (like a human sperm or egg cell). So you have two sisters. They each have 100% of Dad's DNA, since Dad only has one set of chromosomes to all of his offspring. Meanwhile, each daughter is 50% genetically similar to Mom (just like a human daughter would be). If you average 100% and 50%, you see that bee sisters are 75% genetically similar, while they're only 50% genetically similar to Mom.
What does this mean? The theory of Kin Selection suggests that this sister relatedness is why natural selection favors worker bees that don't lay their own eggs but instead help their mom (the queen) lay eggs. Each worker is biologically "better off" helping her sisters than she would be helping her daughters by laying eggs.
Strange strange strange.
*blinkblink* Wow! I just posted the thing from a little fact book I got from the library, but I should check it out again and give you the address to write to them and tell them they were wrong. -- That was some serious science there, and I always sucked at science, so my head's spinning a little.