Check out When Ferns Don't Look Like Ferns by Christopher Taylor on Catalogue of Organisms. The concept of alternating generations is an important concept that everyone should understand. All plants undergo alternation of generation to a greater or lesser degree. Here's an interesting way to think about the concept from the Biology course notes at the University of Miami.
If animals were to undergo alternation of generations, then imagine that you are the diploid individual (sporophyte). Your mother, the gametophyte, would be haploid, and would look completely different from you (maybe like a SmurfTM). Your grandmother would be diploid, and look like you. Your own offspring would look like your mama the SmurfTM, your grandchildren would look like you, and so on.
[Image Credit: Lewis & Clark]
4 comments :
I found the smurf description today. I'm happy to say it gets a little macabre shortly after the part quoted...
Thanks for all the links, Larry - I really do appreciate it.
IIRC, some cnidarians also do the alternating haplo/diplo generation thing. For that matter, so do we all -- except that sperm and eggs aren't usually thought of as distinct organisms.
The difference between our life-cycles and alternation of generations is that the haploid stage of our life-cycle doesn't undergo cell division and growth. Admittedly, this is largely a difference of degree rather than kind - seed plants are still regarded as undergoing alternation of generations, but their haploid stages are only a few cells in size.
Your Haploid Heart - a short story by "James Tiptree, Jr." a pseudonym for Alice Sheldon, used this as a plot device. Circa 1968-70, IINM.
fusilier
James 2:24
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