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Biomedical Ephemera, or: A Frog for Your Boils

@biomedicalephemera / biomedicalephemera.tumblr.com

A blog for all biological and medical ephemera, from the age of Abraham through the era of medical quackery and cure-all nostrums. Featuring illustrations, history, and totally useless trivia from the diverse realms of nature and medicine. Buy me a coffee so I can stay up and keep the lights on around here!
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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.

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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.

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Born in 1707, Carl Linnaeus would rise to such a level of greatness that the philosopher Jean-Jaques Rousseau once said “Tell him I know no greater man on earth,” and was heralded by many of his contemporaries and apostles as Princeps botanicorum - the Prince of Botany. This praise was not without merit: he’s the reason we name almost everything in biology the way that we do. Prior to Linnaeus, the science dealing with naming, organizing, and classifying organisms, called taxonomy, was a disorganized and confusingly complex mess. The word taxonomy is derived from an irregularly-conjugated Ancient Greek word taxis which means arrangement, and the Ancient Greek suffix -nomia, derived from the Ancient Greek word nemein, meaning to manage. Linnaeus had a passion for botany, and while he went to school to study medicine, his long-term goals always included learning about plants. At 25, he won a grant to travel to Lapland and document the local flora and fauna. While there, he began to classify the flowers he found with what we now know as the bionomial classification system - from the Latin bi, meaning two, and nominus meaning name. Prior to this system, species were given long, many-worded descriptive names, and there were several competing outlines for classifying plants and animals into groups, none of which were particularly accurate or helpful to a scientist not intimate with the specific branch of biology the outline was designed for.  The binomial classification system uses two identifiers for a species - the “generic name” (also known as its genus), and the “specific” name (also known as the species). Linnaeus introduced this system in his book Systema naturae, first published in 1735. Even though the first edition was basic and just twelve pages long, it introduced to the scientific community a system that was simple, understandable, easy to remember, and easy to add new species to. Throughout his life, Linnaeus and his apostles continued work on Systema naturae, and by its 10th Edition in 1758, it classified over 4400 species of animals, and 7700 species of plants.

Portrait of Carl Linneaus by Hendrik Hollander, 1853, in the public domain.

Image from Haeckel’s Tree of Life in the public domain.

Guest post for Kids Need Science.

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Egg of a Phoebe and seven consecutive days of growth.

Phoebes, like most passerines, are altricial birds.

Another way that birds can be classified is whether they're altricial (from Latin alere, meaning "to nurse, to nourish"), meaning they're born helpless and blind, or precocial, where they're relatively mature and mobile upon hatching. 

The spectrum between altricial and precocial is wide, and there's no set formula for which reproductive strategy birds use. In general, though, passerines (the perching or "song" birds), herons, woodpeckers, and birds of prey are altricial.

Book of Birds Common to Town and Country. National Geographic Society, 1915.

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Galliphasis albocristatus (now Lophura leucomelanos hamiltoni) and Galliphasis horsfieldii (now Lophura leucomelanos lathami

The White-Crested Kalij Pheasant and Black-Breasted Kalij Pheasant.

Pheasants and other fowl (such as domestic chickens, ducks, and geese) are some of the most well-known precocial birds. Born with open eyes and fluffy down, with "adult" (juvenile) feathers growing in shortly after birth, precocial birds generally require less care from their parents than altricial chicks. The range of precocial nature is broad, though, and precocial birds still need protection and care from their parents.

Most birds that have only one parent caring for them after hatching are precocial, and most tree-nesting birds with two parents are altricial, but there are no set lines how birds raise their young.

Proceedings of the Zoological Society of London. 1858.

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Struthio camelus and Galbula fuscicapilla [now Galbula tombacea tombacea] - The Common Ostrich and White-Chinned Jacamar

The ostrich belongs to the paleognathae, while the jacamar belongs to the neognathae.

There are two superorders (a phylogenetic classification) of the the class Neornithes - the Paleognathae, or "old-jaws", and the Neognathae, or "new-jaws". The palates and beak structures of the paleognathae are much more closely related to reptilian jaws, and the superorder evolved significantly before the "new-jaws" came about. The flightless ratites (ostriches, kiwis, elephant birds, cassowaries, etc) and the flying tinamous of South America are all paleognathae.

All of the other extant birds (27 of the 29 orders) belong to the Neognathae. Everything from the birds of prey to the hummingbirds to the finches and sparrows falls under this classification. 

Transactions of the Scientific Meetings of the Zoological Society of London. 1858, 1854.

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Thylacoleo ("marsupial lion") skull fragments

Richard Owen received and described these skull fragments in 1859. The extraordinary difference in one of the teeth presented to him led him to question the initial proposition that this was simply another extinct placental mammal. Comparing the mandibular structure and tooth structure to dasyures and thylacines versus the mandibular structure of the placental lion showed him that this was a marsupial mammal.

On the Fossil Mammals of Australia Part I. Richard Owen, 1859.

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Triaxeopus cornutus
This octopus’ species is currently under debate. It was known as Octopus cornutus (Owen) for a while, and was considered to be in the “Octopus horridus” group. Horrible octopus. Horrible horrible octopus.
Transactions of the Zoological Society of London, Volume XI. 1885.
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