2007-08-23 17:26:08 · 4 answers · asked by fashionistaqt 3 in Science & Mathematics ➔ Biology
scientists have discovered atoms made up of the same basic chemicals and the different chemical combinations determine what eventual form they take. So they can then see the slight variations of the chemical combination which can tell them how closely related the compounds are to each other.
2007-08-23 17:38:14 · answer #1 · answered by Mr. Bumpkins 2 · 0⤊ 0⤋
The near-universality of the genetic code in biological life. The same codons code for the same amino acids, in almost every organism from bacteria to you.
2007-08-24 15:07:33 · answer #2 · answered by Anonymous · 0⤊ 0⤋
DNA. For instance, humans and chimpanzees share about 98.5% of their DNA. Even humans and rodents share about 90% of the same DNA.
Also, so-called junk DNA (DNA that serves no current purpose) is like fossil DNA in that, while it might not be used in the current organism, it is the DNA used in other related organisms.
2007-08-24 09:07:44 · answer #3 · answered by Joan H 6 · 0⤊ 0⤋
Their DNA, specifically Base Sequence (you know, those A, T, C, G things). A full answer will take a couple days to type up, please consult your biology textbook (I'm assuming your a student) or talk to your biology professor.
2007-08-24 01:30:10 · answer #4 · answered by quantranpharmd@sbcglobal.net 1 · 1⤊ 0⤋