Birdcage

Birdcage (pronounced burd-keyj)

(1) A cage for confining birds (built traditionally with wire or wicker and used also as bird cage & bird-cage).

(2) Something that in form (at any scale) resembles (even vaguely) the construction of a birdcage.

(3) In aviation industry slang, the airspace over an airport and the aircraft there in flight.

(4) An area on a racecourse where horses parade before a race (“paddock” preferred in US use).

(5) In US slang, a used-car lot (now rare).

1480–1490: The construct was bird + cage.  Bird was a pre-900 form, from the Middle English byrd, from the Old English bridd & brid (which in the Northumbrian dialect was “bird”) (young bird, chick; feathered, warm-blooded vertebrate animal of the class Aves).  The Old English bird was an unusual collateral form of bridd and originally meant “young bird, nestling” whereas the typical Old English for bird was fugol, related to the noun fowl, of uncertain origin with no known cognates in any other Germanic language (speculated links to umlaut dismissed by etymologists).  Because birds are a creature doubtlessly noticed and in some form named by people since the early days of human evolution, it’s not surprising it believed variants in Middle English may go back to “an ancient period”.  From the early to mid-fourteenth century, “bird” increasingly supplanted “fowl” as the most common term.

Cage dates from 1175–1225 and was from the Middle English cage (and the earlier forms kage & gage), from the Old French cage (prison; retreat, hideout), from the Latin cavea (hollow place, enclosure for animals, coop, hive, stall, dungeon, spectators' seats in a theatre), the construct being cav(us) (hollow) + -ea, the feminine of -eus (the adjectival suffix); a doublet of cadge and related to jail.  The Latin cavea was the source also of the Italian gabbia (basket for fowls, coop).  The noun (box-like receptacle or enclosure, with open spaces, made of wires, reeds etc) typically described the barred-boxes used for confining domesticated birds or wild beasts was the first form and from circa 1300 was used in English to describe “a cage for prisoners, jail, prison, a cell”.  To “rattle someone's cage” is to upset or anger them, based on the reaction from imprisoned creatures (human & animal) to the noise made by shaking their cages.  The noun bird-cage (also birdcage) was in the late fifteenth century formed to describe a "portable enclosure for birds", as distinct from the static cages which came to be called aviaries.  The verb (to confine in a cage, to shut up or confine) dates from the 1570s and was derived from the noun.  The synonyms for the verb include crate, enclosure, jail, pen, coop up, corral, fold, mew, pinfold, pound, confine, enclose, envelop, hem, immure, impound, imprison, incarcerate, restrain & close-in.  Cage is a noun, verb and (occasional) adjective, caged & caging are verbs (used with object) and constructions include cage-less, cage-like, re-cage; the noun plural is cages.  Birdcage is a noun; the noun plural is birdcages.

The term gilded cage (often heard in the form “trapped in a gilded cage” describes a place (or situation) which superficially is attractive but is in some way constraining; a comfortable but confined situation.  The point of the “gilded cage” is the “effective confinement” is achieved not by the “cage” but by the unwillingness of the confined to relinquish the luxury of their “gilded lifestyle”; it’s thus a self-imposed “imprisonment”, certain comfort valued more than the uncertainties of freedom.  The term is thought to have been coined by the writers of the popular song A Bird in a Gilded Cage (1900).  History (some of it recent) is littered with examples of those “trapped in a gilded cage” and overwhelming they’re well-bred women, compelled for various reasons (dynastic, financial, political etc) to marry someone not of their choice.  A classic example of the adage “for everything you do there’s a price to be paid”, the best documented are the most miserable but the phenomenon is an illustration of the way what ultimately matters is not the situation in which one finds oneself but how one reacts.

Consuelo Vanderbilt (circa 1900), oil on canvas by Paul César Helleu (1859–1927).

Consuelo Vanderbilt (1877-1964) was the most illustrious of the American “dollar princesses” who crossed the Atlantic to marry increasingly impoverished members of the British aristocracy.  Unhappily (and tearfully), aged 18, she became Duchess of Marlborough, diligently and dutifully (for a while) fulfilling the role her father’s money had purchased.  The French painter Paul César Helleu was noted for his portraits of society women of the Belle Époque and, working on commission, he was not above flattery but there’s no doubt he captured the beauty of the slender Consuelo and they may have had had an affair, a diversion not uncommon among dollar princesses chaffing against the bars of their gilded cage.  While in the history texts most in gilded cages are there because they led tortured, unhappy lives, there were some who resolved to “make the best of things” and just try to enjoy the gild: taking the rough with the smooth as it were.  F Scott Fitzgerald (1896–1940) in The Great Gatsby (1925) described Daisy Buchanan as a “golden girl” who had opted for the security of marrying money and was thus consigned to life as a “beautiful little fool” in a “gilded cage of class and gender politics.”  There are worse ways to live and as George Bernard Shaw (GBS; 1856-1950) observed, while money may not buy happiness, surely it is better to be miserable and rich than miserable and poor.   

Lindsay Lohan in The Birdcage, Flemington Racecourse, Melbourne, Victoria, Spring Carnival Derby Day, 2 November, 2019.  The outfit paired a Leo & Lin Venus Asymmetric Scarf Skirt with a Morgan & Taylor Leya Boater Hat.

The origin of the curious use of “birdcage” to describe the enclosed area where horses are saddled and walked before and after a race lies in an architectural analogy, the space enclosed traditionally by light iron railings, often decorative, painted white and closely spaced.  Spectators standing beyond the perimeter looked at the horses, much as one looks at birds inside an aviary; the metaphor thus “perspectival”.  In truth, the usually the circular or polygonal enclosure didn’t really resemble a large ornamental cage but the construction of the ironwork did recall the sides of a “birdcage” although obviously there was no need exactly to replicate the design, horses being unable, Pegasus-like, to “fly away”.  The term remains in common use in the UK, Australia and New Zealand where it had become part of the “social scene” of race days, the photographs published on society pages or Instagram often taken from “the birdcage”; at some tracks the spectator area has been remodelled for exactly that purpose with appropriate promotional backdrops.  In North America, used of “birdcage” in this context is rare, “paddock” the preferred term.

A similar linguistic adaptation was the “bullpen” (in baseball, an enclosed area for pitchers to practice in or “warm up”), the word possibly borrowed from rodeos where it literally was the (well-fenced) holding area for bulls.  In baseball, “bullpen” became a collective noun for pitchers and functioned as a synecdoche.  From the sport, it spread and came to be used figuratively to describe (1) “a place for someone or something to get prepared for some purpose” and (2) a military prison or its enclosing stockade.  Some decades after bullpen entered the vernacular of the sport, leagues were formed for women’s baseball and although in ranching the term “cowpen” (fenced area for holding cows) was well-known, baseball sensibly decided its nomenclature etymologically was detached from biological sex so assembled female pitchers also warmed-up in a bullpen and despite a recent trend towards gender-neutrality in sporting terminology, “bullpen” survived as fossilized baseball jargon.  Linguistically uncontroversial in the sport was “birdcage mask” which was the protective mask worn by catchers, the “birdcage element” referring to the thick wire structure protecting the face while still permitting adequate vision.

Lindsay Lohan (birdcage scene), Rumors (Official Music Video) from Speak (2004).

The origin of the use in baseball is contested although all seem to agree it came into use very early in the twentieth century.  One explanation is that by then it had become common for late-coming spectators to be cordoned off in a “standing room” area in “foul territory” (to the sides of the field where any ball hit was deemed “out of bounds”) and, noting the laggards were “herded like cattle”, “bullpen” was borrowed from the rodeo.  When those areas were re-purposed as the pitchers warm-up space, the designation stuck and the notion relief pitchers were once viewed “bullish” in temperament is thought one of baseball’s many myths.  An alternative theory is the use was at least influenced by the outfield fences at baseball grounds once often displaying advertisements for Bull Durham tobacco and in front of these relief pitchers would wait to be called into play and the use was thus associated with the billboards but for this there’s no documentary evidence. 

The Berghof, circa 1940.

By definition, a birdcage is of course “something in which one keeps one’s pet bird” but they can be also, certainly in their more elaborate forms, a decorative piece of furniture, a symbol of domesticity in the same way George Orwell (1903-1950) in Keep the Aspidistra Flying (1936) used the Aspidistra plant as an identifier of the middle-class though in fairness to the reputation of the perennial herbaceous plant, their popularity in English houses owed much to them being among the species most tolerant of the sometimes smoky atmosphere in an era when coal and wood burned on open fireplaces was a common form of heating.  They were thus an ideal house plant, being tolerant of neglect and suited to shade while their luxuriant growth meant they were effective oxygenators of air high in CO₂.  

Art Nouveau brass birdcage on conforming tripod stand.  The piece featured a domed tops, lift-out trays, swing perch and two small bird-seed feeders.

Tough, the Aspidistra wasn’t exactly “unkillable” but one really had to try and the plants thus were for generations something of a middle class fixture; it was in this sense Albert Speer (1905–1981; Nazi court architect 1934-1942; Nazi minister of armaments and war production 1942-1945), in his (sometimes reliable) memoir Erinnerungen (Memories or Reminiscences) and published in English as Inside the Third Reich (1969) noted the birdcage in Adolf Hitler’s (1889-1945; Führer (leader) and German head of government 1933-1945 & head of state 1934-1945) country house, some years before it was enlarged in the sprawling complex centred on the Berghof:  “After Berchtesgaden came the steep mountain road full of potholes, until we arrived at Hitler's small, pleasant wooden house on Obersalzberg.  It had a wide overhanging roof and modest interior: a dining room, a small living room, and three bedrooms. The furniture was bogus old-German peasant style and gave the house a comfortable petit-bourgeois look.  A brass canary cage, a cactus, and a rubber plant intensified this impression. There were swastikas on knickknacks and pillows embroidered by admiring women, combined with, say, a rising sun or a vow of ‘eternal loyalty.’  Hitler commented to me with some embarrassment: ‘I know these are not beautiful things, but many of them are presents.  I shouldn't like to part with them.’”  Speer made no mention of a canary or any other bird sitting in the cage and nor is there a reference in contemporary accounts; that is in keeping with Hitler’s known views on how animals should be treated and while his attitudes to humanity proved reprehensible, those on wildlife were quite enlightened.

Art Deco birdcage.

Although there’s obviously some functional overlap, as well as birdcages, there are birdhouses, coops, aviaries, pigeon lofts.  A birdhouse is a “small house” for birds (and known also as a nest box).  Made usually of wood and mounted somewhere the residents will be protected from ground-dwelling predators, birdhouses are outdoor structures designed not to imprison wild birds but provide them a shelter where they can build nests.  A coop (in this context) is a place where birds are kept but while a birdcage is for a household pet, a coup is for productive (egg-laying and sometimes feathers or meat) birds and are enclosures built outside, partially enclosed (“chicken coops” the best known).  The word aviary has a wide vista and can be anything from a relatively small structure housing two or more birds to vast zoo-like areas in which there may be a mix of captive and wild creatures.  A pigeon loft (known also as a dovecote) is a specialized type of birdhouse, often placed on a building’s roof or other elevated spot in which domestic pigeons are bred and housed, usually for use in the sport of pigeon racing; the element “loft” tends to be used irrespective of the location of the structure.  A synonym was columbarium, from the Latin columbārium, the construct being columb(a) (pigeon) +‎ -ārium (place for) and because the sport became popular among the aristocracy of the Ancien Régime (circa 1500-1789) in France, the construction of columbaria because something of a contest (al la the “size race” in luxury yachts between today’s billionaires) and architects were engaged to design large, elaborate structures, sometimes emulating the style of the owner’s chateau.

Birdcaged: An airliner's dimmed cabin.

In the airline industry, “birdcaging” is a term which has come into vogue among passengers; it describes the request from cabin crew to close window blinds or (in aircraft configured with electronically dimmable windows) turn down the settings.  Apparently, if passengers don’t conform, the staff will enforce the onset of darkness.  Theories have circulated on the sites where disgruntled passengers complain about the antics of airlines (they are most active sites) with the most popular suggestion being it’s an attempt to keep the cabin’s environment “subdued”, encouraging “better behaviour”.  The airlines seem not to have commented and “birdcaging” is neither acknowledged industry jargon nor admitted to be any company’s policy.  Flight attendants have however taken to TikTok to subdue the debate, claiming airlines “encourage” the dimming to created “a comfortable environment for those who wish to sleep”.  Those keeping birds in cages will note the calming effect of placing a shroud over the wires, emulating night-time.  At least one flight attendant did concede: “I will say this does affect the calmness of the cabin, but that is not the reason we do this.”  From all this, bird-caged passengers will draw their own conclusions.

Coming maybe within a decade to economy class near you: A depiction of a  “windowless” airliner.

Whether windows will continue to be fitted to passenger aircraft isn’t clear because the manufacturers have been attempting to tempt decision-makers (Flexjet in 2025 signed a contract to buy 300 of Otto’s Phantom 3500 nine-seat executive jets) with windowless winged tubes, outside views (or anything else) emulated with shaped-screens which form part of the cabin lining.  The manufacturers say eliminating the windows will make airframes lighter, stronger and cheaper to produce.  It would also lower running costs and emissions because (1) even with flush-fitting fittings, there is some drag induced by the window frames and (2) the heat-soak from sunlight means more energy has to be expended to maintain cabin temperatures.  Additionally, without windows, passengers will be less exposed to radiation and although not many would fly frequently enough for the effect to be measured, it would benefit cabin crew.  Depending on what’s displayed on the screens, the experience could be surreal or hyper-realistic because HD (high-definition) cameras mounted in the fuselage enable the display (using seamless OLED (organic light-emitting diode) panels of a more expansive vista than is possible through a small window.  For now, although flight attendants would probably prefer passengers to be sedated upon taking their seats, bird-caging us will likely remain plan B.

C3 Chevrolet Corvette T-Top birdcage.

From its debut in 1953, the Chevrolet Corvette’s body has always been made from non-steel composite materials ranging from simple GRP (glass-reinforced plastic and better known as fiberglass) to materials of increasing complexity so rust has never afflicted the external panels but beneath all those curves and angels is much vulnerable ferrous metal including the frame and “birdcage”, the latter an object of veneration or despair, depending on its condition.  A crucial component in the overall strength and structure of some Corvettes, the birdcage was first integrated into the design when the C2 (1962-1967) was released and the same concept was used for the C3 (1968-1982): a reinforced frame surrounding the cabin, the nickname from the overall shape which vaguely recalled a birdcage.  Similar in outline to the “safety cell” for which Mercedes-Benz was in 1952 granted Patent 854157 (rigid passenger cell with front and rear crumple zones), the birdcage consisted of boxed steel channels with pillars running from the base of the windshield (A-pillars), along the rear of the cabin, and down to the frame kick-up behind the seats.  Although not really a complex piece of engineering, the fact that so integral to the car is the structure, for extensive repairs to be performed considerable disassembly is required and the cost of out-sourcing such a task often can exceed the value of the car; economics thus suggest it’s usually advisable to find a car with birdcage in sound condition, repairs often financially viable only if the car is rare (ie with a highly desirable specification or even a celebrity association).  A visual inspection is best left to experts because unless it has just emerged from a comprehensive restoration, the birdcages on all C2 & C3 Corvettes will have at least some light, surface rust but it can take an expert eye to tell the difference between that and rot which demands attention.  Fortunately, the Corvette community is vibrant with publications and on-line guides detailing the features & foibles of the structure.

Troubled birdcage: Rusted C3 windshield frame left-lower outer corner (left) and a replacement corner component (1968-1972) @ US$199.00 from Corvette Central.

On both the C2 & C3, there were two variants of the design, one for the coupe (T-top in the C3) and the one for the roadster (the last such C3 made in 1975) but all shared the susceptibility to rust, especially if used in areas with high salt-exposure (coastal regions or places where the stuff was spread on icy roads) and the part most often affected severely was the “Windshield Frame Lower Outer Corners”, replacement sections available and in two different versions for the C3, reflecting the design changes in the post 1973 cars.  However, while the birdcage's most afflicted components, the windshield frame’s outer corners are not unique and the hinge pillars & lock pillars (including the body mount at the bottom) also are notably rust-prone.  Restoration of C1, C2 & C3 Corvettes is in many ways among the easier in the industry because (1) the mechanical components are a simple design, (2) there’s much interchangeability of parts with other GM vehicles, (3) the after-market supply of components is extensive and (4) tiresome bits like plastics and electronics are relatively few.  So, all that’s needed is time, skill and money but there are still aspects in the process that distinguish the work of a first-class operation and often small details can be barely noticed except by experts.  One vital but sometimes neglected step is to ensure the steel platform is never bonded before the application of a zinc chromate primer, a strong corrosion inhibitor used in aviation and marine applications since the 1930s.  While the product now comes in a convenient rattle-can, for those wanting a protection layer that likely will last a century, there is aviation-grade polyurethane in “yellow zinc” and “green zinc”, much used in the restoration of World War II airframes.  A Corvette’s raw birdcage thus treated should outlast even a youthful owner and manufacturers can supply the stuff in a wide color palette with specialists able to mix poly-primer in colors matching original shades.

C4 Corvette structure diagram from Mobile Web-Cars.

To call what was used on the C4 Corvette (1984-1996) a “birdcage” was a bit of a gray area because although routinely so described, materially and structurally it was quite different from the classic template set by the C2 & C3.  What was carried over was welded steel structure surrounding the windshield frame, A-pillars, roof rails, B-pillars and rear window frame which created a defined passenger safety cell distinct from the outer composite body panels so it seems reasonable still to use the term but the C4 did not have a “stand-alone” frame onto which the body was mounted, the “birdcage” being an integral part of the frame.  There were a number of design imperatives which dictated the path chosen for the C4 and it was built with a uniframe in which front and rear frame sections were integrated, thereby providing greater rigidity so no longer was the “birdcage” a kind of bolted-on” internal scaffold but an inherent part of the whole.  The C4 was the last Corvette in which something recognizably “birdcagesque” would appear.

Chevrolet’s technical rendering of the C8’s structure.  In engineering, materials science and computing, much has advanced since 1962.

However, the structural integrity the birdcage in 1962 provided needed still to be achieved but the “brute-force” approach of the C2-C3-C4 era was replaced with more advanced techniques and by the time the mid-engined C8 was released in 2019, the platform structurally would have been unrecognizable to anyone familiar with the earlier generations.  The C8 is built around a core element (the so-called “backbone” or “spine”) which can be visualized as a large aluminum tunnel running down the centre of the car and from this the chassis gains its primary torsional stiffness; it was something like bringing the chassis of the 1962 Lotus Elan into the modern age.  The body panels are almost all non-structural and while there is (as is now universal) a reinforced “safety cell” around the cabin, this is protection of occupants in the event of an “impact incident” (better known as a “crash”).

The Birdcage: The Maserati Tipo 60/61 (chassis #2549, clothed & exposed).

Upon released in late 1962, the structure in the C2 Corvette gained the nickname “birdcage” because of the shape but before that, there was the Maserati “Birdcage”, the Tipo 60/61 (1959-1961) so dubbed because it departed from the typical approach of those building space fames in that instead of relatively few, thick tubes and sections, Maserati used many more but they were slender.  Observers were much taken with the apparent delicacy of the construction and although the engineers assured all the intricate latticework of some 200 chromoly steel tubes (welded often in triangulated form in the points of highest stress) was a design delivering both lightness and rigidity to match the more robust-looking creations.  Those admiring the intricacy were struck more by the resemblance to the thin wires of birdcages.  

Mercedes-Benz 300 SLR (W196S, upper) & 300 SL (W198, lower).

One of the reasons the Maserati’s skeleton looked so delicate was that the space-frame had become associated with Teutonic-flavored construction like that used by Mercedes-Benz for its 300 SL & 300 SLR.  Both shared the same method of construction but despite the names and the visual similarity between the two, there were few common components beyond the nuts, bolts & screws.  The 300 SL (W198; 1954-1963) was a road car while the SLR (W196S; 1955) was a lengthened version of the W196R Formula One Grand Prix car with a sexy body and an enlarged (though somewhat detuned) straight-eight engine; in the sport, it would be the last of the straight-8s.

Scale model of Maserati Typo 60/61 Birdcage by CMC.

The final and most remarkable Maserati birdcage was Tipo 63 Birdcage which featured a mid-mounted 3.0 litre V12.  The Tipo 60 & 61 used front-mounted four-cylinder engines in displacements of 2.0 & 2.9 litres and although there were problems which never wholly were solved (although the reliability did over time improved), the platform enjoyed some success because its forgiving nature lent it excellent handling characteristics and in long-distance events, the lack of power was somewhat offset by the modest fuel consumption and relative low tyre wear, time not spent in the pits as valuable as seconds shaved off lap-times.  Unlike some of its competitors, Maserati did not have the financial resources to “keep up with the times” and develop from scratch a mid-engined sports car so the factory took the approach familiar to many an American engineer and hot-rodder: put in a bigger engine.

1961 Maserati Birdcage Typo 63.  Although installing the V12 didn’t realize the hope-for success, the car will always have a place in the annals of “great moments in exhaust systems”.

Actually, the V12 wasn’t that much bigger than the largest of the four cylinder units used but, with a pedigree beginning with a brief (though unsuccessful) career in the Maserati 250F Grand Prix car, it certainly delivered more power.  Because it was a “relatively” simple matter of blending an existing engine and existing platform, the project quickly was accomplished and Maserati had a mid-engined car on the grid before anyone else and one which could top 305 km/h (190 mph) on long straights.  Unfortunately, placing the big lump of a V12 to the rear upset the Birdcage’s fine balance although one did place fourth in the 1961 Le Mans 24 Hours endurance classic (a place where a 190 mph top speed was unusually valuable), a result which proved to be the marque’s high-water mark in the famous event.

Exoskeleton & Endoskeleton

Exoskeleton (pronounced ek-soh-skel-i-tn)

(1) In zoology, an external covering or integument, any hardened external structure, as the shells of crustaceans or the scales and plates of fishes and reptiles, especially when it is of the nature of bone.

(2) All hard parts, such as hair, teeth, and nails which develop from the ectoderm or mesoderm in vertebrates (generally used only in technical literature).

(3) A wearable robotic machine used for aided or augmented mobility.

1841: The construct was exo- + skeleton.  The prefix endo- was used as a word-forming element meaning "inside, within, internal.  It was from the Ancient Greek ἔνδον (éndon) (within; inner; internal) from the primitive Indo-European en-do- (an extended form of the root en (in)).  Skeleton was from the New Latin skeleton (bones, bony framework of the body), from the Ancient Greek skeleton soma (dried-up body, mummy, skeleton), from the neuter of σκελετός (skeletós) (dried up, withered, dried body (and as a noun: parched; mummy), from σκέλλω (skéllō & skellein) (dry, dry up, make dry, parch), from the primitive Indo-European (s)kelha- (to parch, wither); related was the Ancient Greek σκληρός (sklirós) (hard).  Exoskeleton is a noun; the noun plural is exoskeletons or exoskeleta.

Model Kate Upton (b 1992) making visible parts of her endoskeleton, Halloween Party, 2011.

Skelton was an early variant form.  The noun use of Greek skeletos passed into Late Latin as (sceletus), hence the French squelette and the rare English skelet (1560s), the Spanish esqueleto & the Italian scheletro.  The meaning "bare outline" was first recorded circa 1600; hence the term "skeleton crew" from 1778 used to describe minimal staffing, the skeleton key a similar allusion to some of a structure being removed.  The phrase "skeleton in the closet" (source of secret shame to a person, family or institution) is from 1812 and thought an adoption from the imagery in the fable Bluebeard (1697) by Charles Perrault (1628-1703). Exoskeleton was in 1841 coined by by English paleontologist Sir Richard Owen (1804–1892).  Exoskeleton has become more widely used in recent years because of the interest in fields such as engineering, robotics and medicine in using external structures, often to augment or replace human functions.  As early as the 1960s, the "exoskeleton look" became fashionable among architects who would no longer conceal features like plumbing pipes

Trilobites

Trilobite variants.

Trilobite (pronounced try-low-byte) translates literally as “three lobes".  Often casually referred to as bugs or sea-bugs, in taxonomy, all trilobites actually belong in the class of trilobite in the phylum arthropod and within the class are ten orders.  It’s not known how many species of trilobites existed but almost 21,000 have thus far been identified in the fossil record, their numbers and variety leading them to be regarded as one of history’s more successful animals.  They inhabited all the seas and oceans and endured some three-hundred million years, surviving several mass-extinction events.  Their long duration, their structure and living habits meant they became a common and frequently discovered fossil, noted since antiquity although the first attempt scientifically to classify one seems to have been by Wan Shizen of China who, in 1689 described trylobite pygidia (tails) as "batstones".  The first known scientific drawing was by Welsh botanist, the Reverend Edward Lhuyd (1660-1709) whose sketch of a trilobite was published in "The Philosophical Transactions of the Royal Society.  The drawing, now classified as being a Ogygiocarella debuchii, was then (not unreasonably), called the "flatfish".

Truly ancient, trilobites pre-date the Cambrian explosion (some 540 million years ago) and went extinct only towards the end of the Permian extinction event (some 250 million years ago) which ended the Paleozoic age which had lasted some 290 million years.  However, the earlier events took their toll, a few orders vanishing after the Ordovician event (some 445 million years ago) while the Devonian event (some 370 million years ago) removed all but one order, that last survivor dying out in the Permian event.  Why such a successful and prolific creature could not endure these extinctions remains a debate, the more popular theories including (1) environmental change happening with such rapidity there was no time for evolutionary adaptation and (2) the needed sources of nutrition vanishing because organisms lower in the food-chain went extinct.  All shared the same basic structure, having three lobes: a left pleural, a middle axial and a right pleural lobe, their bodies divided into a cephalon (dead), thorax (middle), and pygydium (tail).  Trilobites had a thick, protective exoskeleton which formed a hard calcite shell, something like that of the modern crab and is the reason for their frequency in the fossil record, the exoskeletons usually the only part to survive although, in the rare cases where certain surrounding conditions exist, traces of soft tissue such as antennae can survive fossilization.  As a trilobite grew, it molted its exoskeleton, and many of the fossils which exist are molted frames rather than dead creatures.

Before & after avian intrusion: 1952 Mercedes-Benz 300 SL (W194), Carrera Panamericana, Mexico, November 1952.

In nature, exoskeletons evolved over thousands of generations through the interplay of natural selection and adaptation to prevailing environmental conditions but with man-made objects such things, in cases of immediate need, can within hours be fashioned.  Returning to the circuits for the first time since the end of World War II (1939-1945), Mercedes-Benz had enjoyed immediate success with the new 300 SL (W194) race car which, despite being underpowered, proved its mettle with a combination of robustness, reliability and outstanding aerodynamics which both increased performance and improved fuel economy.  The W194, ten of which were built, is often referred to as “the first gullwing” (although the configuration had in 1939 been seen on a one-off Bugatti and was not uncommon in aviation and nautical use) but the distinctive doors were introduced only after those enforcing the regulations of sports car at Le Mans ruled the 300 SL’s original “doors” were no such things and were merely “elaborately framed windows”.  With re-designed doors fitted, the W194 promptly delivered the factory a 1-2 result in the 1952 24 hour endurance classic.

1952 Carrera Panamericana: The winning 300 SL in the factory museum.

Concluding things that year was the third Carrera Panamericana, a gruelling endurance event of eight stages over some 3,100 km (1,925 miles) between 19-23 November.  With typical thoroughness, the factory shipped three W194s along with a large support staff and all was going well until the lead car collided with a large bird (contemporary articles variously reporting the unfortunate creature as a vulture or buzzard) which smashed through the windscreen at an impact speed in excess of 215 km/h (135 mph), stunning the co-driver and leaving him bloodied.  Shook awake, he recovered and when the car reached the service point a new windscreen was fitted and, as a precaution against other vultures (or whatever) seeking vengeance, eight metal bars were fitted, the ad-hoc birdcage designed to keep them out, not in.  Without further avian “events”, the W194 repeated the result from Le Mans by finishing 1-2 and, fully restored, the winning car is part of the collection of the Mercedes-Benz Museum in Stuttgart.

1968 London-Sydney Marathon: The 1968 Porsche 911S which finished fourth (left) and after a full restoration (right).  A zoologist would insist this is only a "semiexoskeleton" on the basis of the partial coverage. 

As all in the Northern Hemisphere understand, in Australia, on land, sea & air, all the wildlife will try to kill you.  Noting this, when Porsche’s competition department prepared its three entries for the 1968 London-Sydney they limited their concern about sharks and crocodiles to a single paragraph in the drivers’ instruction sheets and decided the main threat to the cars were wandering “giant” kangaroos and low-flying wedge-tailed eagles (a bird with a wingspan wider even than Mexico’s vultures).  The first event of its type in the modern era, the 1968 London-Sydney Marathon spanned half the globe over a distance of 12,237 miles (16,934) and the route shows how times have changed, stages in Iran & Pakistan included; neither country now places many organizers of events would include in their itineraries but in 1968, kangaroos were still deemed more a threat than terrorism.  Accordingly, the factory designed a kind of exoskeleton, a robust external roll cage which essentially was the W194’s “birdcage” but “on steroids”.  As originally conceived, the structure had been of more modest proportions and while the final result may look like “overkill”, things were “beefed up” following one of the drivers writing off a rented VW Beetle after colliding with a kangaroo during pre-event testing in Australia.  Impressed by the extent of the damage, the engineers produced an impressively strong protective cage, content that whatever else might go wrong, it wouldn’t be a kangaroo which ended the venture.  Porsche 911S #58 finished fourth, victory going to a Hillman Hunter #75, one of the more improbable machines to win an international endurance event.

1968 London-Sydney Marathon: The winning 1968 Hillman Hunter (left) and restored 1967 Pakyan 1725 (right), the Iranian variants often noted for their additional bling.  Unlike the cautious Germans, most teams fitted only rudimentary additional protection against kangaroos and such; some ruefully later casting envious glances at Porsche's exoskeleton. 

In fairness, though an unlikely competition car, the Hillman Hunter (the “mainstream” model in the “Arrow” range which would sold also as “badge-engineered” Sunbeam, Singer & Humber variants) was a success in many countries, lasting in Europe from 1966 until 1979 although its most extraordinary longevity was achieved in the Islamic Republic of Iran.  In 1966, during the reign of Mohammad Reza Pahlavi (1919–1980; last Shah of Iran 1941-1979) assembly from CKD (completely knocked down) packs had begun with the car sold as the Paykan (پیکان, Romanized as Peykān and literally “Arrow”) and, unlike many things, it survived the 1979 revolution to continue to flourish under the rule of Grand Ayatollah Ruhollah Khomeini (1900-1989; Supreme Leader, Islamic Republic of Iran, 1979-1989), full local manufacture starting in 1985.  Although theologically uncompromising, there’s no record of the Imam having complained of the presence on his assembly lines of a product from شیطان کوچک (Sheytān-e Koochak) (the UK & Israel being “Little Satan” and the US شیطان بزرگ (Sheytān-e Bozorg) “Great Satan” although in the West the terms are often misunderstood because in flavour of Shia Islam practiced in Iran, Satan is a pathetic rather than fearsome figure).  When in 1979 Grand Ayatollah Ali Khamenei (1939-2026; Supreme Leader, Islamic Republic of Iran 1989-2026) became supreme leader, the Pakyan carried on and although production of the salon finally ended in 2005, the pick-up variant continued to be sold for another decade, the last not leaving the line until almost 50 years after the first Hunter was sold in the UK.  From the modest Hunter, the ayatollah's got their money's worth.

Exoskeleton cars

MVE Exocet (left) & Exomotive’s Exocet Sport V8 (right).

Exoskeleton vehicles are numerous on farms, mine-sites and such but rarely seen on public roads.  They do though have a niche for those who want something which sacrifices just about everything (aerodynamics, weather protection, doors etc) for the nimbleness only extreme light-weight can deliver.  An example is the MVE Exocet, released for public sale in 2010.  It’s an inventive approach to the kit-car concept and takes the classic front-engined, rear-wheel drive approach, based on Mazda’s Miata (the MX-5, introduced in 1989 and a kind of clone of the Lotus Elan of the 1960s but without the problems), the advantage with the Japanese platform being its unusual sub-frame which permits the removal of the body, leaving the engine, drive-train and suspension as a rolling assembly to be transplanted to the Exocet chassis.

Because of the light weight, even when using sensible four-cylinder engines the Exocet delivers high-performance but the Americans in particular can’t resist the idea that just about any car can be improved by the installation of a V8 and quite outlandish power to weight ratios are possible.  An indicative example of Exomotive’s Exocet Sport used a 525 horsepower (LS3) version of one of the later evolutions of the small-block Chevrolet V8 which, fully fueled, weighed in at 1690 lb (767 kg, the 2026 Formula 1 regulations set a minimum dry-weight (ie excluding fuel) of 768 kg).  Because it possible to buy, off the shelf (as a “crate” engine), V8 engines with about the same power as a F1 power-plant generates, although there was be something a weight penalty, the potential does exist to build a two-seater roadster with a similar power-to-weight ratio and there are jurisdictions which even allow such a thing to be registered for use on public roads.  Opinions would differ on whether such a build is a good idea but the little machines, if the V8 was tuned more for low and mid-range torque rather than ultimate power, would seem to have great potential in competitions such as short-course events and hill-climbs although the dubious aerodynamics would render it less suited to high-speed tracks.

Art and money: Porsche 934 (left) by Benedict Radcliffe (b 1976) sold for US$249,002 while Comedian (a banana duct-taped to the wall, right) by Maurizio Cattelan (b 1960) realized US$6.2 million.

The exoskeleton concept inspired English artist and sculptor Benedict Radcliffe to create a number of small scale tubular steel sculptures in the shape of cars including the Lancia Stratos (1973-1978), Lamborghini Countach (1974-1990) and Ferrari F40 (1987-1992), mostly powdered-coated in lurid colors.  Usually, they sell for several thousand US dollars but in early 2025, one in 1:1 scale in the shape of a Porsche 934 sold for US$249,002; in a nod to history, it was painted in the same fluro-orange used for the Jägermeister livery used for the race cars in 1979-1977 and rolled on period-correct centre-locking BBS wheels shod with Avon slick tires.  At that price, it was little different from what one would pay for a new Porsche 911 GT3, straight from the showroom floor.  Still, it’s less than the US$1.5 million which is typical of what’s been paid in recent years on the rare occasions a 934 is offered for sale.  Produced between 1976-1977, Porsche built 31 934s, simply for the purpose of creating a version of the 930 (the 911 Turbo, 1975-1978) which would comply with the FIA Group 4 (GT Cars) rules (the 935 was the companion Group 5 (Special Production Cars) project).  The art market cannot be assessed with any form of conventional metrics but in paying a quarter-million odd for a tubular structure, one gets quite a lot compared with the Italian visual artist Maurizio Cattelan’s Comedian, (a banana duct-taped to the wall); a couple of months earlier, at auction, it had gone under the hammer for US$6.2 million.

Endoskeleton (pronounced en-doh-skel-i-tn)

(1) In zoology, the internal skeleton or framework of the body of an animal (generally the bony or cartilaginous skeleton of vertebrates).  Certain invertebrates, such as sponges and echinoderms, also have endoskeletons.

(2) For most (non-technical) purposes, a synonym for skeleton.

1838: The construct was endo- + skeleton  The prefix exo- was used as a word forming element in words of Greek origin meaning "outer, outside, outer part" and was used from the mid-nineteenth century.  It was from the Ancient Greek ἔξω (éxō) (outer; external) and was related to ex (out of).  Endoskeleton is used almost exclusively in the biological sciences.  For most general purposes, it’s synonymous with skeleton which is the default assumption of use because it’s familiar from humans and most familiar animals.  Endoskeleton is a noun; the noun plural is endoskeletons or endoskeleta.

The nicely defined shoulder blade and ribcage definition of Lindsay Lohan's endoskeleton.

The word endoskeleton may not have been needed had all creatures on earth had “conventional” skeletons like humans, cats, dogs, fish and such; there would have been just “skeletons”.  Of course, architects and engineers likely would have been unable to resist coining “exoskeleton” there seems no better word to describe an externally-located superstructure.  Both an endoskeleton and exoskeleton are structural frameworks to some degree (sometimes wholly) supporting and shaping an organism’s body and which form an animal evolved to adopt was a product of history and environment.  That’s best illustrated by those with hard outer shell (really the ultimate exoskeleton) which functions as a kind of armor-plate.  Among man-made objects, both models are used and easily identified although exoskeletons (such as the futtocks in nautical design) probably are more common in anything with a “skin” including buildings, aircraft and ships.

Endoskeleton cars

The Birdcage: The Maserati Tipo 60/61 (chassis #2549).

Endoskeleton cars are far from uncommon but some make the concept more obvious than others.  The Maserati Tipo 60/61 (1959-1961) gained the nickname “Birdcage” (by which it’s almost always known) because observers were much taken with the delicacy of the construction.  By the late 1950s, space-frames had become familiar to race-car builders but they were usually robust-looking arrangements whereas Maserati had rendered an intricate latticework of some 200 chromoly steel tubes welded often in triangulated form in the points of highest stress, the design delivering both lightness and rigidity.

Mercedes-Benz 300 SLR (W196S, upper) & 300 SL (W198, lower).

One of the reasons the Maserati’s skeleton looked so delicate was that the space-frame had become associated with Teutonic-flavored construction like that used by Mercedes-Benz for its 300 SL & 300 SLR.  Both shared the same method of construction but despite the names and the the visual similarity between the two, there were few common components beyond the nuts, bolts & screws.  The 300 SL (W198; 1954-1963) was a road car while the SLR (W196S; 1955) was a lengthened version of the W196R Formula One Grand Prix car with a sexy body and an enlarged (though somewhat detuned) straight-eight engine.  Despite appearing much more substantial than the Maserati's birdcage, the German space-frame was remarkably light.