Cofty, as I told you. I don't know, I'm not a botanist or zoologist. Not sure why you are harping on this? Look at an Amoeba dubia or Camelia japonica (if that is what you mean by Japonica)? A beautiful flowering plant, yet far removed from us humans. Amoeba is a one-celled organism. Why would their genome be bigger? Good question.
Here’s a possible answer. Might be the fact that the DNA of the single-celled organism happen to be so extensive to have resulted in a limitation of that species' adaptability? A very sloppy little computer program may well serve its simple function even though it is inefficiently written; yet, it is not likely to be useful as the hub for building a more complex program. Perhaps one of the apprentices worked on those two (as well as the cockroach and mosquito), who knows? Makes me think of Terry Pratchett, one of my all-time favorites. Now that’s a gentleman that had a spectacular imagination. Rincewind’s Australian visit is called “The Last Continent.” Do yourself a favor and read it. You need to lighten up. I stand by what I wrote. Compare that to our computers and computer programs. We don't even come close:
... man is undoubtably the most complex information-processing system on earth. The total number of bits handled daily in all information-processing events occurring in the human body is approximately 3 x 10²⁴. This includes all deliberate as well as all involuntary activities, the former comprising the use of language and the information required for controlling voluntary movements, while the latter includes the control of the internal organs and hormonal systems. The number of bits being processed daily in the human body is more than a million times the total amount of human knowledge stored in all the libraries of the world, which is about 10¹⁸ bits.
Quite a few people are six feet tall. If unraveled the DNA molecule of any cell in one’s body is approximately seven feet long. The information in a single DNA strand is the equivalent of many sets of Encyclopedias. Think about it, the fertilized ovum is the size of a pinhead. That nucleus supplies all the information to construct a person.
Some interesting discussions on the Internet, dealing with above two. But it seems, nobody knows for sure.
Here's a few interesting observations by a botanist, Ilia Leitch, Research Scientist at the Jodrell Laboratory at Kew, concerning Paris japonica (Japanese canopy plant): 'We were astounded when we discovered that this small stunning plant had such a large genome - it’s so large that when stretched out it would be taller than the tower of Big Ben.
'Some people may wonder what the consequences are of such a large genome and whether it really matters if one organism has more DNA than another. The answer to this is a resounding “yes, it does”, and the consequences operate at all levels from the cell up to the whole organism and beyond. In plants, research has demonstrated that those with large genomes are at greater risk of extinction, are less adapted to living in polluted soils and are less able to tolerate extreme environmental conditions – all highly relevant in today’s changing world.'
This brings us back to the comparison of the computer programs, large and clunky ones and sleek and compact ones.