Bacteria and Death
Country: United States
Date: September 2007
Would a species with more genes be more advanced than a species
with less genes?
Not necessarily. There is no clear definition of what "more advanced" means,
if anything, in evolution and adaptation. Evolution is not a directional
process headed toward any thing we might as humans think of as "advance."
More specifically to your question, if by advanced you mean more complex in
structure or behavior, there is still no linear correlation between number
of genes and complexity. This is an extremely interesting subject with lots
of new discoveries and ideas emerging. See work by Richard Dawkins, Stephen
J. Gould, Niles Eldredge and many others.
A larger genome does not mean more advanced organisms. There have been many
studies trying to understand why genome size does not correlate with
organism complexity. To read more about this, do an internet search on
Notice I have said _genome size_ and not _number of genes_. It's relatively
simple to calculate genome size. It's much more difficult to determine which
sequences in an organism's DNA are actually producing proteins as opposed to
those that are non-coding sequences. As a result, there's a lot more data on
genome size than number of genes. Those organisms that have larger genomes
do not necessarily have more genes.
Hope this helps,
There is no relationship between genome size and complexity; many single celled
eucaryotes contain more DNA than a human cell. Although this seems paradoxical,
the answer is that alot of DNA is non-coding DNA which we would not call genes.
For example a human haploid cell contains enough DNA to code for approximately
500,000 genes but is estimated to contain only around 25-50 thousand genes.
This excess DNA is referred to a "junk" DNA.
Ron Baker, Ph.D.
Are you talking about more genes, or more DNA in total? Most people would
agree that humans are the most complex creatures, but we don't have
significantly more genes than other animals. The estimated number of genes
in humans is about 25,000 which is about the same as mice. The newest
research shows that it's not necessarily how many genes you have, but which
genes are expressed, or active.
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Update: June 2012