I consider myself lucky to be among the minority of people who have ever seen a platypus. I spent a few days in eastern Australia a few years back, and had dreamed about spotting a duckbill in the weeks leading up to my trip. Once I set foot on Aussie soil, I was determined to find one. I had to find the right people, however, to help me find them--they're very elusive.
Once hooked up with the right people, we set out for a streamside in a quiet rainforest. It was a rainy afternoon, and we waited for dusk. Platypuses (or platypi, if you prefer--they both sound funny!) are crepuscular creatures, meaning that they're active at dusk and dawn. During the day, they're holed up in stream- or lake-side burrows. We waited for what seemed like forever, getting soaked. As it grew darker and darker, I began to lose hope--maybe I would not get to see one, afterall. Then, in a quiet whisper, the guide said, "There," as he pointed upstream. Sure enough, moving smoothly toward us, was a platypus. As if on cue, he circled around right in front of us, looking for food. It was much smaller than I had expected--males only reach about 20" in lengh, and females about 16". A second platypus also made its way down the stream. It was a once-in-a-lifetime experience to spot one of these guys, and I was thrilled to have seen them. Unfortunately, I have no proof, as the guide discouraged photographs as to not scare them.
Platypuses are possibly the most unusual animals around today. They're classified as monotremes (egg-laying mammals), of which there is only one other species--the echidna (also native to Australia). While they have been considered mammals, they share characteristics of birds and reptiles, too. They have fur and rear their young on milk, but they also lay eggs and the males produce venom. They're sometimes referred to as living fossils, as ancestral platypuses existed alongside dinosaurs 4.5 million years ago!
Researchers at the European Bioinformatics Institute in Oxford have recently analyzed the DNA blueprint of the platypus and have revealed its genetic makeup. Eway Birney, the head reseacher on the genome project, stated, "The platypus looks like such a strange blend of mammalian, bird-like, and reptilian features and now we know that the genome is an equally bizarre mix of all of these. It's much more of a melange than anyone expected."
What I'm now wondering is whether platypuses will still be filed under the Class Mammalia? Or perhaps Aves or Reptilia? I know that in order for us to try and make sense of things that it needs to be classfied under one class. But who's to say that Mammalia is the best place for the platypus?
In a decision that is months overdue (4 months to be exact), the Interior Secretary listed the polar bear as threatened under the Endangered Species Act. The reason for their threatened status is habitat loss--the apparent change in climate is causing sea ice to melt rapidly. Polar bears spend much of their time on the ice hunting seals and doing other things that polar bears do. Ice melted to record low numbers last summer, and officials from the National Snow and Ice Data Center predict extreme low numbers again in 2008. If the sea ice melting trend continues the way it's been going, 2/3 of the polar bears could be gone by 2050.
