Plants to Non-Plants?

In another forum, some creationist had posted that conundrum as a supposedly great difficulty for evolutionary biology.However, there exist several species of parasitic plants, many of which do not photosynthesize, and which often resemble fungi more than plants. However, they often continue to produce flowers and other features that get them recognized as plants; Rafflesia produces some especially large ones. Though one might want to give one's Significant Other a super bouquet of these flowers, be warned that Rafflesia flowers smell like rotting meat; they are pollinated by flies.There is evidence that some protists and "fungi" have gone a similar route. Oomycetes or water molds are most closely related to diatoms and brown algae; they are essentially algae that have lost their chloroplasts. Likewise, apicomplexans like Plasmodium and Toxoplasma have "apicoplasts" that are vestigial chloroplasts that only make fatty acids and the like.Animals have also gone the fungus-like route. Sacculina carcini and other rhizocephalans ("root heads") are blob-shaped parasites that send tendrils into their hosts. However, they are really parasitic barnacles whose adults have abandoned barnacle-like features other than being attached to some substrate; their larvae are nauplius larvae that resemble other barnacle larvae -- larvae which seek out some suitable substrate on which to rest and become an adult.A creationist may respond that that is really "degeneration" and not really evolution; but though parasites often subtract features, they also often gain adaptations that are helpful for their lifestyle.

I find Brad McFall's response depressing. It's as if he had barely understood what I was writing. And from his mostly-incomprehensible verbiage, I discover: Which only supports my suspicion. Checking on some discussions of parasitic plants, I discover that they send tendrils into their hosts in fungus-like fashion. The same is true for parasitic barnacles; I'm sure that both Rafflesia and Sacculina could easily be mistaken for fungi until they start producing flowers and nauplius larvae, respectively.

Brad McFall, you have continued to go off on odd and unintelligible tangents. Would it be possible to have some friend of yours proofread your postings?I challenge you to check out these species:Rafflesia arnoldii
Sacculina carciniand see what you come up with. In the absence of flowers and nauplius larvae, and in the absence of gene-sequencing technology, could these organisms be distinguished from fungi? If so, what would you need to look at in order to make that distinction? "Body" and tendril details? Cell-wall chemistry?I specify absence of gene-sequencing technology because that makes the identification task almost too easy. If one was not sure about the affinities of Rafflesia or Sacculina, one would sequence some ubiquitous molecule like SSU rRNA and compare it to the big library of known sequences. And once one has a hint as to what to look for, one could look for chloroplast-related genes in Rafflesia, Hox genes in Sacculina, and similar subgroup-specific genes.[This message has been edited by lpetrich, 12-01-2003]

Zhimbo:
What exactly is the conundrum?Some creationists seem to think that plants cannot evolve from non-plants, or that non-plants cannot evolve from plants. So what might qualify as a non-plant evolving from a plant?