Posts tagged Skeleton

biomedicalephemera:

Man (Homo sapiens sapiens), Cow (Bos taurus), and Ram (Ovis aries)
The structure of the ruminant animals varies considerably. It’s important for the artist to recognize the vertebral layout and rib structure, even of animals that are covered in thick wool or fur. Wild bovids (such as bison) and aurochs have extended thoracic vertebrae that form a “hump” over their shoulders.
A Comparative View of the Human and Animal Frame. B. Waterhouse Hawkins, 1860.

biomedicalephemera:

Man (Homo sapiens sapiens), Cow (Bos taurus), and Ram (Ovis aries)

The structure of the ruminant animals varies considerably. It’s important for the artist to recognize the vertebral layout and rib structure, even of animals that are covered in thick wool or fur. Wild bovids (such as bison) and aurochs have extended thoracic vertebrae that form a “hump” over their shoulders.

A Comparative View of the Human and Animal Frame. B. Waterhouse Hawkins, 1860.

Save your babies!
(1 in 8 babies will die before 1 year)
Death watches…
Mothers! Give smart care, snatch it out of his hands.
Surprisingly, unlike many other countries directly affected by WWI, France did not experience a significant uptick in infant, childhood, or maternal mortality during the later years of the war. Though they lost many more young men than most countries, and the fertility rate (babies per fertile woman) dropped as a consequence, the survival of the babies that were born actually increased. In other countries, such as Spain and Italy, food shortages and oppressive regimes ended up creating a situation where their childhood mortality increased nearly 150% by the last year of the war.
However, a 1 in 8 (12.5%) mortality rate is still abysmal, compared to today’s standards. Cholera, viral diarrhea, typhoid, measles, scarlet fever, and all manner of other infectious diseases were still prevalent in Europe. By 1950, the infant mortality rate had decreased to 52 out of 1000 babies (0.05%), and by 1993, the rate had fallen all the way to 6 out of 1000 babies.
Image:Chromolithograph for the Red Cross by Alice Dick Dumas, 1918. Now part of the Wellcome Archives in London.

Save your babies!

(1 in 8 babies will die before 1 year)

Death watches…

Mothers! Give smart care, snatch it out of his hands.

Surprisingly, unlike many other countries directly affected by WWI, France did not experience a significant uptick in infant, childhood, or maternal mortality during the later years of the war. Though they lost many more young men than most countries, and the fertility rate (babies per fertile woman) dropped as a consequence, the survival of the babies that were born actually increased. In other countries, such as Spain and Italy, food shortages and oppressive regimes ended up creating a situation where their childhood mortality increased nearly 150% by the last year of the war.

However, a 1 in 8 (12.5%) mortality rate is still abysmal, compared to today’s standards. Cholera, viral diarrhea, typhoid, measles, scarlet fever, and all manner of other infectious diseases were still prevalent in Europe. By 1950, the infant mortality rate had decreased to 52 out of 1000 babies (0.05%), and by 1993, the rate had fallen all the way to 6 out of 1000 babies.

Image:
Chromolithograph for the Red Cross by Alice Dick Dumas, 1918. Now part of the Wellcome Archives in London.

cabbagingcove:

THE COVEY WOTS GOT A KNACK OF TAKING PEOPLE OFF
Caricature of death as a gentleman, standing on a tombstone.
Image:
Illustration by satirist G.S. Tregear, ca. 1820. Now at the Wellcome Library, London.

cabbagingcove:

THE COVEY WOTS GOT A KNACK OF TAKING PEOPLE OFF

Caricature of death as a gentleman, standing on a tombstone.

Image:

Illustration by satirist G.S. Tregear, ca. 1820. Now at the Wellcome Library, London.

Rainbow Snake - Farancia erytrogramma

The rainbow snake is a large North American colubrid that lives along the Southeastern coastline of the US. A subspecies that lived in Lake Okeechobee was declared extinct in 2011, but the common rainbow snake (Farancia erytrogramma erytrogramma) is non-threatened at this time.

These guys are non-venomous, highly glossy, and also known as “eel moccasins”, for their habit of eating “conger eel” salamanders. Despite their bright, shiny colors, and their length of over 4 feet long, these snakes are extremely difficult to spot in the wild. They stay under swampy underbrush, are largely aquatic, and hunt their prey at night. Without specific traps or highly skilled herpetologists, the chances of seeing one in the wild are extremely slim, but many herp farms and experienced snake owners like having them around for their aesthetic appeal.

Top: Three-toed sloth (Bradypus tridactylus) skeleton and depiction
Bottom: Two-toed sloth (Choleopus hoffmanni) skeleton and depiction

Despite their superficially similar appearances, and their overlapping ranges, the two-toed and three-toed (well, two-fingered and three-fingered, as they all have three toes) sloths had very different evolutionary paths, and only came out so similarly due to convergent evolution, thanks to their rainforest habitat. They are not very related at all, it turns out. Their last common ancestor (LCA) existed around 39 million years ago (mya) - to put that in perspective, the LCA of ALL current mammals (humans, bats, whales, sloths, all of us) was probably around 65-60 mya, and the LCA of humans and chimpanzees was only 9 mya! Seriously, they are NOT very related. They’re both about as related as they are to the other members of their order - the South American Anteaters.

The two-toed sloths evolved from the ancient Megalonychidae, which includes the Megalonyx and other skeletal giant sloths, whose ancestors lived in South America between ~7 mya and 5000 years BCE. Though obviously not helped by the new immigrants, the giant sloths had already suffered significant declines to their population due to environmental changes by the time that humans arrived. We may have eaten a few here and there, but we did not cause their extinction, unlike many of the giant Pleistocene mammals of North America. These days, there are two species of two-toed sloth - Hoffman’s and Linnaeus’.

Three-toed sloths, however, we’re not quite sure about. Either they evolved in ways we don’t have complete links to, or they evolved from specimens that didn’t leave fossils that we’ve found yet. Like two-toed sloths, we do think that they dwelt on the ground until the Holocene (~12,000 years BCE), but we don’t know for sure. However, around that time, the savannahs and woodland/prairie environments of a lot of Central and South America became replaced by rainforest, which would have caused evolutionary pressure for them to move to the trees. Currently, there are four species of three-toed sloth - the pygmy (critically endangered), pale-throated, brown-throated, and maned.

Both creatures are slow, arboreal (tree-dwelling), and have many insects, fungi, and blue-green algaes (which aren’t actually algae at all…) growing from their fur. The two-toed sloths are slightly quicker than the three-toed sloths (approximately 1650 and 800 ft/hour, respectively - at least on land! Three-toed sloths are actually quicker swimmers than they are on the ground, and two-toed sloths are not so good at the swimming). They generally (but not always) eat different tree species, and often overlap ranges.

Comparative anatomy of the Bactrian and Dromedary Camels, and the human.

Humans domesticated Bactrian camels (Camelus ferus) over 4500 years ago, and Dromedary camels (Camelus dromedarius) even earlier - around 4000 BCE, or 6000 years ago. Domesticated Dromedary camels are so ancient that even the first dynasties of Egypt were thought to use them, from archaeological remains.

While Dromedary camels have survived relatively unchanged in the wild, Bactrian camels have been significantly altered by domestication. They’re shorter, far more amenable to human interaction, and have been bred to have longer fur and greater milk output. There is over a 3% difference in the genetic code between domestic and wild Bactrian camels - more than exists between humans and chimpanzees.

Comparative anatomy as applied to the purposes of the artist. Benjamin Waterhouse Hawkins, 1883.

biomedicalephemera:

Man (Homo sapiens sapiens), Cow (Bos taurus), and Ram (Ovis aries)
The structure of the ruminant animals varies considerably. It’s important for the artist to recognize the vertebral layout and rib structure, even of animals that are covered in thick wool or fur. Wild bovids (such as bison) and aurochs have extended cervical vertebrae that form a “hump” over their shoulders.
A Comparative View of the Human and Animal Frame. B. Waterhouse Hawkins, 1860.

biomedicalephemera:

Man (Homo sapiens sapiens), Cow (Bos taurus), and Ram (Ovis aries)

The structure of the ruminant animals varies considerably. It’s important for the artist to recognize the vertebral layout and rib structure, even of animals that are covered in thick wool or fur. Wild bovids (such as bison) and aurochs have extended cervical vertebrae that form a “hump” over their shoulders.

A Comparative View of the Human and Animal Frame. B. Waterhouse Hawkins, 1860.

North Island Moa (Dinoris novazealandiae), high-class Māori in kakapo and kiwi feather robe, and Haast’s Eagle (Harpagornis moorei)

The Haast’s Eagle (Harpagornis moorei) was the largest known raptor to exist - while there were larger birds that existed, no larger birds of prey have been found in the fossil record so far. It was huge, large enough to easily take away a small human child, and create a significant injury threat to even the largest adult humans.

When the Polynesian people known as the Maori arrived in New Zealand, around C.E. 1250-1300, the Haast’s eagle and moa would have been dangerous and defining creatures in their lives. While the moa was not a big meat-eater, it could kick (and possibly kill) a human more easily than an ostrich can, and would not have hesitated to do so, if threatened.

However, with their already-advanced spears and javelins, and their ingenuity with hunting and shelter-building, the Maori easily overcame the threat of the moa - by 1400, the giant bird was no more.

Unfortunately, with its primary food source gone, the Haast’s eagle also went extinct, shortly after the moa. Today, birds like the kakapo, kiwi, taiko, and takahe, are all critically endangered, because of human influence and habitat destruction. New Zealand’s island environment, with its few airborne predators and unusual evolutionary pressures, has lead to extremely specialized birds, and they unfortunately adapt poorly to a modern world that has feral cats, rats, and poachers. While conservationists attempt to protect them from the pressures of non-island life, there is little telling what the future holds for them.

Images:

Extinct Birds. Lionel Walter Rothschild, 1907.

A History of the Birds of New Zealand. Walter Lawry Buller, 1873.

"Ancient DNA Tells Story of Ancient Eagle Evolution". Art: John Megahan, 2005.

do lions bones have a bonemarrow? — Asked by Anonymous

Yes. All animals that have bones (which includes all vertebrates aside from cartilaginous fish) have bone marrow. Red bone marrow is essential for hemopoiesis (the production of blood cells), and yellow bone marrow is an important nutrient reservoir. Different species have different amounts of each kind of bone marrow, but if it has bones, it has marrow.

[Fun fact: Since sharks and other cartilaginous fish such as rays have no bones, they have to make their blood cells somewhere else - namely the spleen, or a funny organ surrounding the esophagus, called the Leydig’s organ.]

Lion bones on Biomedical Ephemera

Hm. I don’t have much on sharks posted. I should fix that.

Fig 1: Front side of Os Femoris (the femur bone)Fig 2: Back side of Os FemorisFig 3: Underside of Patella, where it moves against the Os Femoris
The femur is, by most measures, the strongest bone in the tetrapod body. Its articulation with the acetebelum of the pelvis forms the freely-moving synovial hip joint, and its articulation with the tibia and patella at its distal end forms the knee joint. These joints accommodate walking, running, and jumping, which are critical activities for the survival of most tetrapods.
At the bottom of the front-facing femur (Fig 1), you can see an articular depression between the two condyles, called the patellar surface. This is where the patella rests. The deeper notch in the back of the femur (Fig 2) provides an articular surface for the many ligaments of the knee joint.
The patella's primary purpose is to provide protection to the crucial structures in the knee. The synovial joint is strong, but if it got damaged when we were still living off the land, it could mean death from an inability to farm or hunt.
Cheselden’s Plates of the Human Bones. William Cheselden, 1814 reprint.

Fig 1: Front side of Os Femoris (the femur bone)
Fig 2: Back side of Os Femoris
Fig 3: Underside of Patella, where it moves against the Os Femoris

The femur is, by most measures, the strongest bone in the tetrapod body. Its articulation with the acetebelum of the pelvis forms the freely-moving synovial hip joint, and its articulation with the tibia and patella at its distal end forms the knee joint. These joints accommodate walking, running, and jumping, which are critical activities for the survival of most tetrapods.

At the bottom of the front-facing femur (Fig 1), you can see an articular depression between the two condyles, called the patellar surface. This is where the patella rests. The deeper notch in the back of the femur (Fig 2) provides an articular surface for the many ligaments of the knee joint.

The patella's primary purpose is to provide protection to the crucial structures in the knee. The synovial joint is strong, but if it got damaged when we were still living off the land, it could mean death from an inability to farm or hunt.

Cheselden’s Plates of the Human Bones. William Cheselden, 1814 reprint.

collectivehistory:

"A Student’s Dream.", R. R. Robinson, 1906
Medical students’ initiation rite of posing for a photo with their dissection cadavers often in humorous circumstances. 
(Source)

collectivehistory:

"A Student’s Dream.", R. R. Robinson, 1906

Medical students’ initiation rite of posing for a photo with their dissection cadavers often in humorous circumstances. 

(Source)

Bone types

Top: Metacarpals (long bones) and carpals (short bones)
Second row, left: Left ulna (long bone)
Second row, right: Scapula and sternum (flat bones)
Third row, left: Sagittal section of the knee joint, including the patella (sesamoid bone)
Third row, right: Thoracic vertebrae (irregular bones)
Bottom: Complete Skeleton

Bones are classified into five groups, organized by shape.

Long bones are longer than they are wide, and are subjected to most of the load-bearing responsibilities in everyday life. These include the humerus, radius, and ulna (arms); fibula, femur, and tibia (legs), as well as the phalanges (fingers and toes), metacarpals (hands) and metatarsals (feet).

They grow from the epiphysis (growth plate) at either end of the bone, and failure of these bones to grow causes the majority of dwarfism cases.

Short bones are as wide as they are long, and provide support, but do not bear heavy loads or move much. These include the tarsals (feet) and carpals (hands/wrists).

Flat bones are broad bones that provide protection to organs, and large areas for muscle attachment. These include the bones in the skull, the ilium, scapula, sternum, and ribs. The flat bones consist of two layers of compact bone, surrounding a layer of cancellous bone, where the majority of red bone marrow exists. In adults, most red blood cells are produced in the flat bones.

Sesamoid bones are bones within tendons, which pass over a joint. The most familiar sesamoid bone is the patella, or knee-bone. These bones provide protection to delicate joints.

Irregular bones don’t fit into any of the above categories. The mandible and vertebrae are irregular bones.

Images:

Atlas and Text-book of Human Anatomy. Dr. Johannes Sobotta, 1914.
Anatomy: Descriptive and Applied. Henry Gray, 1918.
A Series of Engravings, representing the Bones of the Human Skeleton. William Cheselden, 1819.

Views of the Adult Human Skull
Top: Front and side viewsBottom left: Lower surface (underside) of base of skull, displaying the bony hard palate (upper palate), zygomatic arches, and foramen magnum.Bottom right: Upper surface (interior) of base of skull, displaying foramen magnum, sphenozygomatic beam, and temporal beam. The beams are critical supporting structures contributing to the strength of the skull.A Series of Engravings, representing the Bones of the Human Skeleton. Edward Mitchell and John Barclay, 1819.

Views of the Adult Human Skull

Top: Front and side views
Bottom left: Lower surface (underside) of base of skull, displaying the bony hard palate (upper palate), zygomatic arches, and foramen magnum.
Bottom right: Upper surface (interior) of base of skull, displaying foramen magnum, sphenozygomatic beam, and temporal beam. The beams are critical supporting structures contributing to the strength of the skull.
A Series of Engravings, representing the Bones of the Human Skeleton. Edward Mitchell and John Barclay, 1819.

American Flamingo - Phoenicopterus ruber

Flamingos aren’t naturally pink! They get their coloration from beta carotene found in the blue-green algae they consume. The flamingos that consume blue-green algae directly are much pinker than flamingos that primarily consume the blue-green algae secondhand (via zooplankton/brine shrimp). 

Flamingos are also unique in their method of eating - their bills are designed to scoop the bottom sediment and then filter out the mud and silt, leaving only the blue-green algae or the brine shrimp in their mouth. They shake their head back and forth under the water after scooping up the sediment. The big, fleshy tongue of the flamingo pushes water back and forth in the mouth and facilitates the filtering of all that mud. They also swallow their food while their head is upside-down! The meaty tongue used to be considered a delicacy among the Roman elite.

Images:
Nature Neighbors: Embracing Birds, Plants, and Minerals. Nathanial Moore Banta for the American Audubon Association, 1914.

Osteologia Avium; or, A sketch of the osteology of birds. T.C. Eyton, 1867.

One of these things is not like the other…

First row: Walrus (Odobenus rosmarus) skeleton
Second row: Hooded seal (Cystopkora cristata) skeleton
Third row: Dugong (Dugong dugon) skeleton, Brazilian sea lion (Otaria flavescens) skeleton.

*Skulls depicted are of species in the same genus as the skeleton.

Sirenia (manatees, dugongs, and sea cows) and Pinnipedia (the seals, walruses, and sea lions) are often seen as very similar, but they came from very different lineages.

While both came from land mammals (just like all sea mammals), the pinnipeds evolved from a bear-like ancestor, who returned to the sea around 28 MYA. They’re Caniformidae, or dog-like Carnivora.

The sirens evolved from the same ancestor as the hyraxes and elephants, and returned to the sea around 50 MYA. They’re only distantly related to Cetaceans and Pinnipeds.

Vergleicheende Osteologie. Edward D’alton, 1821.