The DNA sequences of all living things have much in common because they ultimately evolved from the same common ancestors. Humans, for example, share about 50% of the same DNA sequences that occur in bananas. This is not as surprising as it might seem at first. Both humans and bananas are made up of relatively similar cells, with features in common, like a nucleus, cytoplasm, mitochondria and, of course, DNA.
A much closer relative, the chimpanzee, shares about 98% of human DNA sequences. Chimpanzees and bonobos are usually considered to be the closest living relatives of humans, even though our evolutionary lines split around four to seven million years ago.
More about DNA:
- The human genome was completely sequenced by 2003. Humans have about 20,000 genes on 23 pairs of chromosomes.
- The creature with the most genes is currently thought to be a kind of water flea, a tiny crustacean which has about 31,000 genes.
- While no two humans are completely genetically identical (not even identical twins), all humans share about 99.5% identical DNA.
