Okay, my slow yet triumphant return has meant I’m a little belated to comment on the recent emergence of the platypus genome.
I’m am very happy about the platypus genome. My Honours research was marsupial based, but if I hadn’t gone and retrieved some platypus genome database information (thanks WUST!), I would not have been able to do some exciting three way mammalian comparisons.
The platypus, and monotremes, in general are a source of further framing issues regarding evolution progression. I tried very carefully to avoid this in my thesis by emphasising that Marsupial/Monotremes weren’t primitive and have unique characteristics, while still offering a voyeur’s window in a world between birds and eutherians (the fancy term for placental mammals – whales, mice, and us).
One of these uniquely monotrematic traits was introduced to me by a young lass who worked with me at the resort. Yes, I knew she was an animal fanatic (after this I suspect could be closet furry), but this definitely required Google verification before I believed it. Brace yourself…
One eager exhibitionist echidna had to be kicked out of the zoo for scaring the kiddies (or probably their red-faced parents) with this waz-dangle, I mean phallic appendage.
This [the echidna penis ejeculates with two heads at a time] resembles very much the way lizards and snakes ejaculate: they have a double penis (named hemipenis), but only one of the two penises is used during the copulation, while the other will effectuate the next copulation/ejaculation. Marsupials (another primitive group of mammals) are now in this matter something between monotremes and placental (evolved) mammals: they do not use half of the penis for mating, but still have a double headed penis, while the echidnas have a reptilian joined hemipenis, with each part of the penis in a marsupial-like fashion. – Softpedia
While we genetic scientists are focusing on the riddle of a sex determining gene(s) in monotremes, I wonder if any developmental biologists will be working out about their other sex bits?