[Southack]

"There are more ways for junk DNA to get into a cell than for it to be lost. For instance, some viruses will pick up other bacterial DNA instead of virus DNA by accident before leaving a host cell; when they attach to some other cell, instead of infecting it with viral DNA, they add in part of the DNA from the cell they just left. There's all sorts of crazy ways for bacteria to pick up junk DNA (or useful DNA)."

So shouldn't we see more junk DNA code in all older species?

[xm177e2]

So shouldn't we see more junk DNA code in all older species?

What is an "older species?"

If all species descended from the same cell, all would be equally "old," in some sense. When a new species branches off from an old one, it does not do so in a pristine state, it carries over most of the mutations the last one had.