"...Platypus (Omithorhynchus anatinus), showing the poisonous spur on the inside of the hind leg on an adult male."
"...The male platypus has “a sturdy erectile keratin spur on each hind leg (Fig. 2) just above the webbed foot, which is connected via a venom duct to a venom (crural) gland lying under the dorsal thigh muscles.” The male platypus aggressively injects venom into his opposition by "erecting the spur, grasping and squeezing the victim between his hind legs, and driving the spurs and venom into the victim’s tissues" (Fenner et al., 1992)."
(Source)
"...The beak, nails, and spurs of the chicken are highly keratinized structures..."
(Source)
Sidney Hugh Reynolds writes in his 1897 “book “The Vertebrate Skeleton” Google throws up:
“Claws should not be confounded with spurs, which are conical horny structures developed on bony outgrowths of the radial side of the carpus, metacarpus, or metatarsus. They occur in a number of birds, but are most commonly developed in gallinaceous birds, by which they are used for fighting. A single spur occurs on the metacarpus in Megapodius[that mound brooder], in Palamedea[a screamer], in Parra jacana and in Hoplopterus spinosus, the Spur-winged plover. The Derbian Screamer, Chauna derbiana, has two metacarpal spurs, borne on the first and second metacarpals. The Spur-winged goose, Plectropterus gambensis, has a carpal spur borne on the radial carpal. Metatarsal spurs are quite common.
The male Solitaire (Pezophaps) has large bony excrescences on the wrist which may, like spurs, have been sheathed in horn and used for fighting.”"...Sometimes the male and female birds of a species are similar in overall size, but show distinct differences in the size, development and/or length of a particular body structural feature. There might be differences in the size or length or development of the bill (beak length), the legs, the neck, the tail feathers, the comb or crest, the flight feathers, the leg spurs, the claws or some other component of the bird's body."
(Source)
The "Trash Bird"
"The native people of Papua New Guinea call the hooded pitohuis "trash birds" and refuse to eat them. Scientists now know why: These songbirds are among the first birds documented to be venomous. "John Dumbacher, an ornithologist (a scientist who studies birds) at the California Academy of Sciences in San Francisco, discovered why in 2009. Holding the birds made him sneeze and itch; it also made his eyes water. Predators foolish enough to eat a hooded pitohui suffer worse consequences. High levels of batrachotoxin, the same toxin used by poison dart frogs, are found in pitohui muscle, heart and liver. If eaten, the toxin interrupts the normal function of a predator’s nerve cells, eventually causing the diner’s heart to stop beating."
(Source)
A SIDE NOTE:
Death by toxic goose. Amazing waterfowl facts
"...Weighing as much as 7 kg, this formidable bird (not a goose in the strict sense, but a member of the shelduck/sheldgoose clade Tadorninae*) bears sharp spurs on its wrists. The birds use these in attacking both other spur-winged geese, and other waterfowl (at least in captivity: a captive individual kept at Slimbridge maintained a territory on top of a small hill. Waterfowl of other species would sometimes climb the hill, get attacked, and die from their injuries).
Anyway… as if this isn’t bad enough, members of this species can sometimes be poisonous. But I don’t mean that they can inject venom with their wing-spurs, or anything like that. Rather, some populations (those in the Gambia) feed on a poisonous beetle (specifically, a member of the blister beetle group (Meloidae)), and then sequester the beetle’s poison into their own tissues (Bartram & Boland 2001). Blister beetles are well known for producing the toxin cantharidin, small amounts of which (as little as 10 milligrams) cause death in humans. The effect of cantharidin on the urinary tract (it results in swelling of the genitalia) means that people have been using it as an aphrodisiac for centuries; the Spanish fly Lytta vesicatori is a blister beetle. So the result of blister beetle ingestion by spur-winged geese is that their flesh is toxic. Eating one can – apparently – result in death (Wanless 2001) [Plectropterus in flight shown below].
While the poisonous tissues of several passerines – notably the various pitohuis, the Ifrita Ifrita coronata and the Rufous shrike-thrush Colluricincla megarhyncha of New Guinea – is now quite well known (this was covered on Tet Zoo back in 2008), they aren’t alone and several other birds are also known to sequester toxins from various animal and/or plant prey. Quail Coturnix coturnix are known to be toxic when on migration, but only certain populations are, and only on part of their migratory journey (e.g., those flying from west Africa to Europe are toxic; those going from eastern Africa to Europe aren’t toxic, but are when they return to Africa in the Autumn). Being poisoned by quail even has a name (coturnism): there are accounts of it in the Bible, and it was so common in the Roman Empire that the eating of quails was banned in the 1st century (Bartram & Boland 2001).
(Source)
BACK ON TOPIC:
There's no denying that dinosaurs and birds share common ancestry which links them, but no matter how hard they may try to place dinosaurs and birds on the same evolutionary branch with birds arising after Cretaceous theropod dinosaurs. No, actually its worse than simply that. Some misinformed people say that birds which existed 125 million years ago "evolved from" dinosaurs which existed 50 millions later.
Such a hypothesis is only with a time machine... its absolutely, beyond any reasonable doubt, impossible and very un-Darwinian of anyone who suggests so.
The Time Machine Hypothesis.
Velociraptor was not bright red enough, so I amped him up a bit.
Doubtlessly, birds and dinosaurs share a common ancestor, and there's no doubt some other similarities may well have evolved through convergent evolution, just like flying reptiles evolved the ability to fly independently and separately apart from birds. Just as insects, flying squirrels, bats... even some species of snakes, etc. developed the ability to glide and fly.
Hollow bones helped high-flying reptiles stay aloft
(Source)
More on "Convergent Evolution" (Source).
Actually though, dinosaurs and birds really don't look THAT similar.
Another cross between mammal, bird and reptile...
Fossil indicates hairy, squirrel-sized creature was not quite a mammal
"...Preserved in the fossil is a clear halo of guard hairs and underfur residue, making Megaconus only the second known pre-mammalian fossil with fur. It was found with sparse hairs around its abdomen, leading the team to hypothesize that it had a naked abdomen. On its heels, Megaconus possessed a long keratinous spur, which was possibly poisonous. Similar to spurs found on modern egg-laying mammals, such as male platypuses, the spur is evidence that this fossil was most likely a male member of its species."
(Source)
7 Poison Animals (Birds, Mammals, Reptiles including "Slow Loris" which is a primate).
(Contains poison on brachial gland on arm while grooming.)
Venomous vs. Poisonous
Although the words “venomous” and “poisonous” are used interchangeably in everyday speech, they are actually fundamentally different. By definition, venom has to be injected into the body, introduced by a bite or a sting. Poison, on the other hand, is ingested or inhaled into the body by the victim. Thus, venomous and poisonous animals are altogether different.
(Source), (Source), (Source)
Phylogenetic Relationship: Monotremes, Marsupials and Placental Mammals.
Perhaps the (marsupial) kangaroo's behavior of kicking as a defense, was genetically inherited from their distant (not so distant) common ancestors, and distant (not so distant) relatives like the rooster who will spur a challenger with his nasty ... spurs.
Perhaps to propose this is mere speculation, but only time, and further fossil evidence can tell.
Questions such as this raised further questions that only professional herpetologists, geneticists and the like could perhaps ever answer. The "spurs" that we have seen on the Boa/Python, are they truly "vestigial limbs"? --or, perhaps they are genuinely "spurs" like those found in the males of birds and monotremes (aka platypus). For now, as far as I am concerned, the jury is out. The "expert" conclusions differ,
The notes on that subject "Python Vestigial Pelvis, Femur and Spur" became so extensive, that I moved all content to a page for discussion all its own.
Question Mark on "Attached to Pelvis" is because the bone is free-floating.
"Skeleton of an Indian Python, showing the tail (left) and ribcage (right). The extra bones attached to the ribs (glued for mounting, but naturally just attached to the flesh without direct contact with any ribs) are half a pelvis and one of the back legs, which pythons and boas have not completely lost. Though they are not the only types of snakes to still have these vestigial legs (appearing as cloacal spurs on live animals), they are the ones that are best known for the feature."
(Source)
By Teresa Bradley Bays, Teresa Lightfoot, Jörg Mayer
"...Spurs are most commonly found on the hindfeet, though some birds possess spurs at the leading edge of the wings." (Wikipedia)
MAMMALS
"To mark their territory, ringtailed lemurs will rub their scent glands (located on their chests and wrists) on trees. The males also have “spurs” on their wrists to make scratches in the trees before they scent mark them."
(Source)
REPTILES
"Male chameleons have a tarsal spur from the time that they are hatched." (See photo). (Source)
BIRDS
Spur-wing geese and... numerous other birds with multiple purposes on both forelimb and hindlimb. An old research paper :
(Source)
Photo of spur-wing. (Source)
More...
"Professor Belov said the echidna did have some venom genes, with low expression levels, which suggested the animal's secretions may have been toxic and used for defence millions of years ago.
''It suggests they were there in the past and they're no longer important,'' she said.
The gradual disappearance of the venom in the spur secretion meant a new role for the gland had evolved, she said. Platypus venom, on the other hand, is highly toxic and can kill dogs. The small number of people who have been stung, typically fishermen or biologists, report excruciating pain that can take months to subside."
(Source)
"The egg-laying mammals — the monotremes, including the platypus and spiny anteaters — are eccentric relatives to the rest of mammals, which bear live young. In addition to laying eggs, other quirks make them seem more like reptiles than our kin."
(Source)
(Yes, and the "missing link" between mammals and birds too).
"...The male platypus has well developed spurs on the heels of its hind feet. The spurs are hollow and connected to a venom gland, allowing the platypus to deliver a very painful kick both in mating competitions and as a defense.[22] Similar, but non-venomous spurs are found in echidnas.[23] Similar spurs have been found in the fossils of several early mammals, and is possibly the primitive condition in mammals as a whole.[24]"
(Source)
Maybe it's a subject for another day ... lots of fun.
Evolution of spurs, fangs, claws, et cetera and their relation to venom and pheromones and all that good stuff, in reptiles, mammals and birds. All the way back to synapsids and diapsids.
(2014)
"Although no fossil evidence of these structures has been found, ancestral monotremes likely had venom delivery systems very similar to that of extant monotremes (see Section 3.1), in the form of an extratarsal spur consisting of cornu calcaris (the spur, which is covered by a keratinous sheath) and os calcaris (the supporting bone). Interestingly, there are several fossils of non-monotreme mammals with evidence of a potential venom delivery system similar to that of the monotremes. These include fossils with what have been interpreted as extratarsal spurs [3,13], and fossils with an os calcaris that may have supported an extratarsal spur [14]. It is thus possible that the extant monotreme extratarsal spur is plesiomorphic, having been retained in monotremes but lost in the therians [14,15]. This implies that many early mammals may have had spurs, and possibly associated venom glands, as a defensive mechanism (Figure 1), although additional fossil evidence is required to resolve this." (Source)
[Therian refers to a member of the Mammalia subclass Theria which consists of marsupial and placental mammals.]
It would make the perfect Christmas Gift. They're so cute.
Awwww, its so sweet and some said they're anti-social and solitary.
Envenomation by a platypus results in a localized, immediate, and intense pain followed by edema and hyperalgesia (increased sensitivity to heat and pressure) (de Plater et al, 1995). The pain associated with a platypus strike is unlike any other in nature. It is extremely intense, and unlike most other animal envenomations, cannot be quelled by morphine. Edema can last up to a week and hyperalgesia can continue for months. The first-aid for an attack is to avoid contact with the site of the sting and restrict movement of the limb (Sutherland, 1983). As stated earlier, the pain cannot be masked by morphine. There is also no antivenin available. The only treatment that has been found to help reduce the pain is anesthetic blockade coupled with narcotic intravenous infusion (Fenner et al., 1992). This works by stopping the conduction and/or transmission of nerve signals. Only then can morphine (or another narcotic) be used to help treat the pain. Fenner et al. (1992) went on to explain that this treatment only helps alleviate some of the pain and must be administered for several days.
(Source)
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