Comments by "broadbandislife" (@broadbandislife) on "Baby Platypus Caught on Camera" video.

  1. AKCHUYALLY their eggs are leathery like those of lizards, not hard-shelled like those of birds. But yeah when European naturalists first got their hands on a taxidermied one in 1799 they considered it a hoax - not unreasonably, as Frankensteining up chimeric taxidermies out of several different critters had a long and storied pedigree. The Wolpertinger out of German folklore is a well-known and prolific example and the platypus is almost as bizarre.
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  2.  @_Breakdown  You can literally find this stuff on Wikipedia in a few minutes ya know, don't need to be any kind of specialist. Platypus electroreception is entirely passive, they don't have specialised field-generation organs like some fish do. (The ability to actively generate your own electric field is technically called "electrogenesis".) The mentioned dolphin is the Sotalia guianensis or Guiana dolphin (aka estuarine dolphin or costero), very much a member of the dolphin family Delphinidae - porposes are the Phocoenidae family and the two are only related on the level of the superfamily Delphinoidae. The "beaked hedgehogs" you're talking about are the echidnas I mentioned. They're also the only extant monotremes besides the platypi, and the ability is presumably inherited from a common ancestor. Fair on the lateral line, I got that mixed up with the fish and amphibian electroreceptive senses being derived from it. The ampullae of Lorenzini are what the cartilagenous fish - sharks and rays - use for terminal homing on prey; you know those distinctive patterns of dots sharks have on their faces? Yeah that's them. Some basal bony fish (reedfish, sturgeon and lungfish) also retain them but most bony fish have lost them. Another lateral line derivative. Cetaceans are the "whales" sensu lato - whales sensu stricto, dolphins and porpoises. The magnetic navigation you're talking about - magnetoreception - is a separate matter (magnetism and electromagnetism aren't the same thing), both much more widely found in nature and considerably less well understood. Even freaking foxes seem to have a version; they appear to be able to locate rodents under cover by the tiny distortions the bioelectric field thereof create in the Earth's magnetic lines. For whatever the Hell reason it apparently works the best when the target is to the north or north-east of the fox. Other peculiar uses include the wandering albatrosses apparently being able to tell the approximate depth of the ocean below them - they stick to waters a kilometre or more deep. (It's not really known how they do this but hard to see how anything other than magnetic sense would do the trick, and they likely have it as navigation aid anyway.) Weird shit, man. While you have a point about completely pure water that's quite moot as you don't find that shit outside laboratories. Any H2O encountered in the wild has varying levels of impurities mixed in.
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  3. Except not. Radars are active sensors - they transmit electromagnetic pulses and then pick up the reflections. What the platypus has is passive electroreception, the ability to sense electric fields and changes therein such as produced by muscle movements etc. which is obviously very useful for locating stuff when you have no visibility. While quite rare in mammals - only the platypi, echidnas and a species of dolphin have developed it - it's dime a dozen among fish (the lateral line and ampullae of Lorenzini) some of which also actively generate their own electric fields for better effect and other purposes (as anyone who's had contact with electric eels or rays can attest). Not unrelated: air is an insulator of electricity, water a conductor. It's the same fundamental difference as between active echolocation (eg. bats and cetaceans) and plain old garden-variety sense of hearing.
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  4.  @_Breakdown  [citation needed]
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  5. ??? It's classified as Near Threatened, the second-best status on the IUCN's Red List. As far as is known it's weathered the intrusions of modern civilizations pretty well which cannot be said of several other examples of local fauna Down Under.
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