3 results found.
... Science Frontiers ONLINE No. 74: Mar-Apr 1991 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Echidna Eccentricities Monotremes: platypus (below); one of two species of echidnas (above) The echidna is one of the monotremes-- an egg-laying mammal. Like its relative, the platypus, it is a strange mixture of mammalian, marsupial, and reptilian characteristics. For example, echidna eggs are soft and leathery, like those of reptiles, but they are brooded in a marsupial-like pouch. The emerging baby echidna has an egg tooth like the birds and reptiles, while the adult has no teeth at all. Rather, it has a narrow snout through which it ingests ants and termites caught on its sticky tongue. In this it resembles the mammalian ant-eaters, which are also toothless but an ocean away from Australia. In fact, the echidna is often called a "spiny anteater" for it has the sharp spines of a hedgehog or porcupine. There are more anatomical peculiarities, but let us focus on the echidna's strange behavior during the mating season. At this time, 2 to 8 echidnas can be seen roaming the Australian bush in "trains" headed by a female with the smallest male acting as a caboose. When mating time arrives, the female anchors herself to a tree with her forelegs. To-gether the males dig a circular "mating rut" up to 10 inches deep around the tree. (Australians have puzzled over these circular trenches for years. ...
Terms matched: 1 - Score: 35 - 15 May 2017 - URL: /sf074/sf074b07.htm
... evolutionary mold and innovate? It's not consistent with the text! The fossil record reveals that a platypus-like creature lived long before the Age of Mammals. These early platypusses had teeth in the adult phase, whereas their modern relatives replace their baby teeth with horny plates -- another innovation. Therefore, far from being a hodgepodge of parts left over from bird and reptile evolution, the platypus has actually pioneered several zoological features. Very curious is the fact that the platypus is in many ways like the beaver -- a very, very distant relative both in distance and position on the Tree of Life. Both platypus and beaver are furry, aquatic creatures with webbed feet and a large, flat tail. We have saved the strangest part for the end! Platypusses, being Monotremes (one-enders) have a common vent for waste and reproduction. Beavers, it turns out, are among the very rare placental mammals that (like the birds) possess a cloaca -- a common vent for urine and excrement. (Hoffman, Eric; "Paradoxes of the Platypus," Scientific American, 264:18, March 1991.) Comment. The "beaver" part just mentioned was not in Hoffman's article; we added it because it underscores the ap parent convergent evolution of platypus and beaver. Reference. For many more platypus curiosities, refer to BMA25, BMA50 in our catalog Biological Anomalies: Mammals I and BMO8 in Biological Anomalies: Mammals II. Information on these books may be found here . From Science Frontiers #75, MAY- ...
Terms matched: 1 - Score: 14 - 15 May 2017 - URL: /sf075/sf075b08.htm
... BME2 Persistence of Certain Mammalian Morphological Forms in the Fossil Record BME3 Explosive Radiations in Mammalian Evolution BME4 Unexplained Extinctions of Large Mammals BME5 The Failure of Evolution to Improve Mammal Survivability BME6 Anomalously Early Fossils BME7 Track-Like Markings in Ancient Strata BME8 Mammals with Histories Known Only from Subfossils BME9 Anomalous Distribution of Mammalian Skeletal Material BME10 Parallelisms in the Mammalian Fossil Record BME11 Pleistocene Dwarfing of Some Mammals BME12 Variations in Mammalian Teeth and Skeletons Show a Definite Direction Very Early Australian Placental Mammals Eurasian Apes as Ancestors of the Great Apes (and Humans) Aquatic Sloths Evolution of Cetacean Osmoregulation Evolution of Giraffe Necks Bipedal Apes (before Humans) BMF BODILY FUNCTIONS BMF1 Water-Breathing in Mammals BMF2 Remarkable Adaptations in Diving Mammals BMF3 Oddities of Digestion BMF4 Perpetual Growth in Mammals BMF5 Limb Generation in Mammals BMF6 Anomalies of Hibernation in Monotremes BMF7 The "Winter Sleep" of Bears BMF8 Freeze-Avoidance in Hibernating Mammals BMF9 Cold-Blooded Mammals (Poikilotherms) BMF10 Transmission to Progeny of Adaptations Induced by Low Temperature BMF11 Inheritance of the Effects of Rotation BMF12 Male Lactation BMF13 Asymmetry in the Function of Mammary Glands BMF14 Pressurized, Sealed Suckling Systems BMF15 The Ability of One Mammal to Control the Sexual Functions of Another BMF16 Correlation of Primate Menstruation with Lunar Phase BMF17 The Delayed-Birth Phenomenon BMF18 Polymorphic Sperm in Mammals BMF19 Pregnancy Rates Correlated with Lunar Phase BMF20 Maternal Impressions in Mammals BMF21 Weeping in Mammals BMF22 Sleeplessness in Mammals BMF23 Curious Types of Sleep BMF24 REM Sleep in Mammals BMF25 Big-Bang Reproduction (Semelparity) in Mammals BMF26 Unusual Deaths of Mammals BMF27 Longevity Increased by Radiation and Hunger Sperm Competition Ear Regeneration BMG GENETICS BMG1 Discordances ...
Terms matched: 1 - Score: 5 - 15 May 2017 - URL: /cat-biol.htm
