Notes from the Field No. 2: Erstwhile Pets

Scarritt Pocket

Mammal fossils lured paleontologists to Oligocene age rocks in Patagonia of Chubut Province, Argentina. The deposits pictured here were discovered by G.G. Simpson heading the Scarritt Expedition in 1934.  This photograph comes from a modern paleontological expedition revisting the area.  Image credit: Vucetich et al. 2014. “A New Acaremyid Rodent (Caviomorpha, Octodontoidea) from Scarritt Pocket, Deseadan (Late Oligocene) of Patagonia (Argentina).”  Journal of Vertebrate Paleontology 34 (3): 689 – 698.

In the 1930s, the reknowned American paleontologist George Gaylord Simpson (1902 – 1984) led a number of fossil hunting expeditions with the American Museum of Natural History to Patagonia in the southern end of South America.  Simpson was very much interested in an assemblage of ancient mammals living in “splendid isolation” on the island continent of South America.  His research centered upon these endemic radiations and their eventual fate when a narrow landmass, the Isthmus of Panama, arose at the end of the Pliocene (approximately 3 million years ago) and began the Great American Faunal Interchange.  While searching for evidence from this epic story of South-meets-North, the expedition lightened their days enjoying the antics of local wildlife they adopted as camp pets.

The vast plains of Patagonia are a barren and savage waste in which man seems an interloper.  Here in the far south of South America nature never smiles. . . Yet Patagonia has its own children, living in constant fear and combat, but somehow contriving to flourish and finding in this desolation a home suited to their own wild temperaments. . . .

Simpson in the Field with Jacket

Simpson at the dig.  A skeleton is carefully excavated, covered in shellac, and bandaged for safe transport.  Image credit: Simpson 1932.

We caught one of the babies [a Darwin’s Rhea, Rhea pennata] and christened him Charita. . . . [he] soon forgot his brothers and sisters and lived with us contentedly, a silly creature with feet much too big for it, its body the size and shape of the egg from which it came (where the neck and legs fit in I do not see), covered with soft down, dark brown and striped with white like a skunk.  His idea of heaven was to wedge himself tightly between two hot pans beneath the camp stove.  When deprived of his sensuous pleasure, he divided his time between trying to crawl into our pockets and trying to scratch his head, laudable ambitions neither of which was ever wholly achieved. . . . He used to sleep with one of us, and soon became a real member of the family.  His cry was a sad whistle, slurring down the scale and ending with a pathetic tremolo. . . . he would come running whenever we called him and would carry on long conversations with us.

Charita the Rhea Chick

Expedition members tended to name their pets after the local language — in this case, “Charita” referred to “ostrich chicks in general.”  Of course, Charita was not actually an ostrich, but a related ratite indigenous to South America known as a rhea.  Drawing by E.S. Lewis.  Image credit: Simpson 1932.

Our long favorite was a pichi [i.e., armadillo] named Florrie. . . . She came to tolerate us as servitors but never displayed any demonstrative affection.  One can no more pet an armadillo than one can pet an egg or, more aptly, a tortoise, and her own attitude was always one of vapid selfishness.  Yet she fully earned her keep.  As she wallowed in a saucer of condensed milk we laughed more at than with her.  She never learned to lap it up cleanly with her long tongue, but must always get her sharp, flexible snout in it too, so that attempts to breathe resulted in convulsive coughs and mighty blowing of bubbles.  She would start to wander off, then suddenly remember the milk, dash back to it in the most business-like way and start drinking again, only to lose interest, wander off again, and repeat the whole process several times.

There was always something vague about Florrie.  Her thick skin seemed to be an index to her mentality and emotions.  Almost the only real emotion she betrayed was when first captured.  Then, if touched, she would suddenly jump, at the same time emitting a convulsive wheeze, a maneuver as disconcerting as the explosion of a mild cigar.  Later she ceased to bother.  If she wandered off when let out, it was rather from absent-mindedness than from any active dislike for our society.  She seemed to think with her nose, and when thus let out for exercise she would trot busily from bush to bush, poking her nose into the ground beneath and sniffing violently.  Once she got away altogether and for several days we mourned her for lost, when one morning she wandered back into camp with her usual air of preoccupation.  The cook, whose special friend she was, swore that she returned for love of us, and another said she had returned for free meals, but I maintain that she had simply forgotten that the camp was there two minutes after she left it, and stumbled on it again quite by accident in the course of one of her sniffing parties.

Florrie the Armadillo

Drawing by E.S. Lewis.  Image credit: Simpson 1932.

These erstwhile pets shared in the daily life of the expedition.  What, if anything, was planned for their ultimate fate is a bit more ambiguous.  Simpson devotes a great deal of space in this popular account to the culinary merits of the local wildlife (a hallowed tradition in scientific expeditions) and both rheas and armadillos were eaten regularly.  Whether the men planned to abandon the animals, eat them, take them back to New York, or have them prepared as museum specimens, that decision soon became moot.  For “. . . .Charita met an untimely end.  He developed an unwholesome appetite for kerosene and, one day, finding a whole pan of this delightful beverage unguarded, he overindulged.  All afternoon, he wandered about vaguely as if something was very much on his mind, or stomach, and next morning he was dead.”  Likewise, Florrie, who was a cheerful presence in camp for several months, ended up being accidentally crushed to death.  Despite these unhappy ends, it is clear that the hapless bumblings of animals like Charita and Florrie were the focus of much entertainment and affection during the long months of isolation grueling in the field.  

Quotation Source

Simpson, George Gaylord.  1932.  “Children of Patagonia.”  Natural History 32 (2):  135 – 147.

Figures: Horned Screamer Gives Directions

Anhima cornuta drawing wing outstretched

Image credit: Naranjo 1986.

“Yes, officer — they headed that way.  I hope you catch those capybaras. . .  they looked shifty as f**k.”

 

About This Image

This figure comes from a behavioral study of Horned Screamers (Anhima cornuta) and shows a lateral one-wing stretch, a type of comfort behavior exhibited by animals loafing around, preening and relaxing.  The odd, thumb-like projection is probably one of the bony metacarpal spurs typical of screamers.  The drawings were made from tracings of 35 mm photographs taken in the field.

These birds do indeed share habitat with giant semi-aquatic rodents, the capybaras.

Learn more about Horned Screamers in a previous post here.

Image Source

Naranjo, Luis G.  1986.  “Aspects of the Biology of the Horned Screamer in Southwestern Colombia.”  The Wilson Bulletin 98 (2):  243 – 256.

Screaming Unicorns: Anhima cornuta

Anhima cornuta by Eduardo Carrion Letort via PBase

Image credit: Eduardo Carrión Letort via PBase.

There is strange honking cry haunting the humid, primaeval wetland forests of the Amazon Basin.  It comes from an appropriately antiquarian-looking beast, the Horned Screamer (Anhima cornuta).

Neither quite like a turkey nor quite like a goose, screamers belong to the Galloanserae, which branches off between the oldest living group of birds, the Palaeognathae (e.g., ostrich, cassowary, kiwi, tinamou), and the Neoaves, which represent over 95% of all extant bird species.  The middle child of modern bird diversity, Galloanserae itself consists of such familiar and often under-appreciated denizens such as chickens, turkeys, quail, pheasants, ducks, and geese.

DSC_0191

Image credit: Yale Peabody Museum / Curious Sengi.

Horned screamers have a rather mind boggling list of anatomical oddities*, but the most obvious is that single thin horn growing out of the top of the head.  Though no published studies specifically examine the function of the horn, it is most likely a display structure since the first appearance of the horn correlates with sexual maturity and many social interactions are marked with a certain amount of head bobbing.  The horn continues to grow throughout life and has been measured to lengths of 15 cm; however, the tip is prone to breaking off.

* Wicked bony carpometacarpal spurs projecting out of the wings!  No uncinate processes on the ribs!  Crackly pneumaticized skin!

DSC_0128

Image credit: Yale Peabody Museum / Curious Sengi.

Anhima cornuta variations

Many variations in the shape of the horn from a population of birds observed in southwestern Colombia.  Image credit: Naranjo 1986.

There is currently no firm consensus about the nature of the Horned Screamer’s horn.  Stettenheim (2000) claims this is a cornified structure growing from the skin and not a feather modified into a bare shaft.  This hypothesis is consistent with Stettenheim’s emphasis on the incredible lability of avian integument to generate novel structures.  In opposition is Prum (2005), who interprets these horns as “entirely tubular feathers”; likewise, this supports Prum’s larger corpus of work on the tubular model of feather development and growth.

DSC_0146

Though the horn is attached to the skull on the left, the horn seems only to be loosely connected to the bone as it is often observed to waggle freely with the movement of the skin. The skull on the right shows a distinct boss or bump where the horn would be positioned.  Image credit: Yale Peabody Museum / Curious Sengi.

While the exact identity and function of the horn remain somewhat mysterious, early observers of the bird could not help ascribing mythical properties to the horn.  In 1659, Otto Keye published a book entitled Het waere Onderscheyt tusschen Koude en Warme Landen, which described the Dutchman’s adventures in Surinam.  In this book, the Horned Screamer is described as using the horn to fight its enemies, but more significantly, the horn was stirred into the waters to purify it of all poisons before the bird took a drink.  This behavior is suspiciously similar to that of the unicorn, which was believed in Europe to possess such a powerful innocence and purity that it could cleanse polluted waters with a touch of its fabled horn.

Unicorn is Found Tapestry_detail

Detail from the famous series of Unicorn Tapestries.  The unicorn kneels down to purify the waters with his horn for the benefit of all his fellow creatures.  Hunting dogs and their masters lurk in the corners.  Image credit: “The Unicorn is Found” from The Unicorn Tapestries, Netherlands, 1495 – 1505 via Metropolitan Museum of Art.

DSC_0244

Image credit: Yale Peabody Museum / Curious Sengi.

The Horned Screamer is currently listed by the IUCN as a species of least concern, despite some previous concern about habitat loss and population decline.  May this delightfully bizarre bird continue long-lived and glorious!

Brasão_de_Tiete

The Horned Screamer is honored as a heraldic device in the coat of arms for the Brazilian municipality of Tietê in São Paulo state. Image credit: Wikimedia Commons.

 

References

Barrow, James H., Jr., J.M. Black, & W.B. Walter.  1986.  “Behaviour patterns and their function in the Horned Screamer.”  Wildfowl 37:  156 – 162.

Naranjo, Luis G.  1986.  “Aspects of the Biology of the Horned Screamer in Southwestern Colombia.”  The Wilson Bulletin 98 (2):  243 – 256.

Penard, Thomas E. & T.C. Penard.  1924/1925.  “Historical Sketch of the Ornithology of Surinam.”  De West-Indische Gids, 6de Jaarg.:  145 – 168.

Prum, Richard O.  2005.  “Evolution of the Morphological Innovations of Feathers.”  Journal of Experimental Zoology 304B:  570 – 579.

Schufeldt, R.W.  1901.  “On the Osteology and Systematic Position of the Screamers (Palamedea: Chauna).”  The American Naturalist 35 (414):  455 – 461.

Stettenheim, Peter S.  2000.  “The Integumentary Morphology of Modern Birds — An Overview.”  American Zoologist 40:  461 – 477.

 

Notes from the Field No. 1: Darwin v. Octopus

Charles Darwin had all the anxieties typical of a recent college graduate:  uncertain of what was to come, depressed by the prospects available in the Real World.  He had already disappointed his physician father once by dropping out of medical school, so he studied theology at Cambridge in order to take up the gentlemanly profession of being a parson.  But young Charles was clearly procrastinating and desperately planning one last hurrah of the naturalist’s life.  Then one late summer’s day, he opened a letter offering him an opportunity to sail around the world aboard the HMS Beagle. . . . 

11000648074_536724f39b_o

The first port-of-call in what would become a five year voyage around the world.  The Beagle landed at St. Jago, Cape Verde Islands off the coast of West Africa.  It was Darwin’s first real intoxicating taste of the tropics.  Image credit: Barrow, John. 1806. “A Voyage to Cochin China, in the years 1792, and 1793.” via The British Library (Flickr)

28 January 1832, St. Jago

Found amongst the rocks West of Quail Island at low water an Octopus.— When first discovered he was in a hole & it was difficult to perceive what it was.— As soon as I drove him from his den he shot with great rapidity across the pool of water.— leaving in his train a large quantity of the ink.— even then when in shallow place it was difficult to catch him, for he twisted his body with great ease between the stones & by his suckers stuck very fast to them.— When in the water the animal was of a brownish purple, but immediately when on the beach the colour changed to a yellowish green.— When I had the animal in a basin of salt water on board this fact was explained by its having the Chamælion like power of changing the colour of its body.— The general colour of animal was French grey with numerous spots of bright yellow. . . . Over the whole body there were continually passing clouds, varying in colour from a “hyacinth red” to a “Chesnut brown”.— As seen under a lens these clouds consisted of minute points apparently injected with a coloured fluid. The whole animal presented a most extraordinary mottled appearance, & much surprised very body who saw it. . . . The animal seemed susceptible to small shocks of galvanism: contracting itself & the parts between the point of contact of wires, became almost black.— this in a lesser degree followed from scratching the animal with a needle.— The cups were in double rows on the arms & coloured reddish.— The eye could be entirely closed by a circular eyelid.— the pupil was of a dark blue.— The animal was slightly phosphorescent at night.

The common octopus, Octopus vulgaris. Image credit: Jatta, Giuseppe.  1896.  “Cefalopodi viventi nel Golfo di Napoli (sistematica).” Fauna und Flora des Golfes von Neapel und der angrenzenden Meers 23 via Biodiversity Heritage Library (Flickr).

30 January 1832, St. Jago

Found another. changed its colour in the same manner when first taken. Caught another: I first discovered him by his spouting water into my face when I certainly was 2 feet above him. When seen in water was of dark colour with rings: being with difficulty removed from a deep hole & placed in a puddle of water swam well & emitted a dark Chesnut brown ink.— he continued likewise to spout water, evidently being able to direct his siphon.— When on land did not walk well having difficulty in carrying its head which it continued filling with air as before with water.— From same cause the animal often made a noise when squirting out water. They are so strong & slippery that one hand is insufficient to hold them.— Whilst swimming generally changed colour & seemed to imitate colour of the rocks.—

Chromatophore

Image credit: Cloney & Florey 1968.

 

Darwin was obviously mesmerized by the way the octopus changed its colors like “passing clouds” and he noted the “minute points apparently injected with a coloured fluid.”  What he saw were chromatophores, specialized cephalopod pigment cells.  Each chromatophore is individually innervated (labeled “Axon” in lower left of the diagram) and equipped with radial muscle fibers that pull the chromatophore from a dense ball of dark pigment into a flat, splayed out pigment field that blossoms with color.  

References

Cloney, Richard A. & E. Florey.  1968.  “Ultrastructure of Cephalopod Chromatophore Organs.”  Zeitschrift für Zellforschung 98:  250 – 280.

The Complete Work of Charles Darwin Online.  John van Wyhe, ed.  2002.  http://darwin-online.org.uk/

Desmond, Adrian & J. Moore.  1991.  Darwin:  The Life of a Tormented Evolutionist.  W.W. Norton & Company.

 

Small beginnings. . . .

This post is part of a series commemorating the 150th anniversary of the Yale Peabody Museum of Natural History.  We will be uncovering the stories behind the first specimens to enter the Peabody collections, as well as some of the most recent.

First specimen acquired for Vertebrate Paleontology:  YPM VP 2125 Plateosauria

DSC_0981_01

YPM VP 2125 Plateosauria. Image credit: Yale Peabody Museum / Curious Sengi.

It is no surprise that this assemblage of rocks does not look like much:  they were blasted out of a 23-foot hole by Solomon Ellsworth, Jr. of East Windsor, Connecticut in 1818.  Ellsworth was constructing a well on his property when he noticed the chalky white bones in the rubble of dark red sandstone.

The unusual find was passed around in local circles of learned men, including a number of professors at the Medical Institution of Yale College, who came to the lukewarm conclusion of “. . . .the possibility that they might be human bones, but did not consider the specimens as sufficiently distinct to form the basis of a certain conclusion (Smith 1820).”  In 1821, a letter was published in The American Journal of Science and Arts that expressed the opinion of Dr. Porter, who was present on Ellsworth’s property when the bones were found.  He deduced the remains came from “some animal. . . . about five feet in length.  The tail bone was easily discovered by its numerous articulations distinctly visible. . . . and by its being projected, in a curvilinean direction beyond the general mass (Hall 1821).”

DSC_0977_01

Many elements — such as those in this right forelimb — have pasted labels, which is not standard for research specimens, but might perhaps reflect this fossil’s history as a teaching specimen. Image credit: Yale Peabody Museum / Curious Sengi.

Another redescription appeared in the same journal decades later in 1855.  Jeffries Wyman stated that the tail vertebrae most resembled a crocodile and noted the similarity of the hollow limb bones to those of birds, both strikingly prescient observations.  The mysterious remains were finally declared to be a Triassic dinosaur in 1896 by O.C. Marsh (1831 – 1899), that grandiose, bearded professor of paleontology at Yale and ambiguous hero of the heady Wild West days of dinosaur collecting.

The exact identity of the fossil has bounced around, but it is currently recognized as an indeterminate sauropodomorph in the clade Plateosauria.  This obscure dog-sized beast was part of a lineage leading to the sauropods, the behemoth long-necked herbivores we fondly remember as Brontosaurus, Diplodocus, Titanosaurus, and others.  From small beginnings arose some of the largest animals to ever live upon this Earth.

DSC_0091

One of the vertebral elements with an illustration of a reconstructed plateosaur skeleton. Image credit: Galton 1971 via Carroll, R.L. 1988. Vertebrate Paleontology & Evolution / Yale Peabody Museum / Curious Sengi.

Despite the rather humble appearance of these bones blown out of Ellsworth’s well, their scientific relevance has been long-lived, with the specimen being cited in publications as recently as 2012.  The bones also have the historical distinction of being the earliest discovered dinosaur fossils in North America verified by recorded literature and an existing specimen.

So how did this subject of lively discussion amongst the physicians, professors, and learned citizens of early 19th century Connecticut find its way into the Yale Peabody Museum?  The world of science was still relatively small and intimately connected by communities of correspondence, so it was a matter of time before the news reached one of America’s most influential men of science, Benjamin Silliman (1779 – 1864).  (Incidentally, he was also the founder and editor of The American Journal of Science and Arts which published the first accounts of the bones.)  As a professor of chemistry, geology, mining, and pharmacy at Yale College, Silliman for many years kept a “Mineral Cabinet” that was filled with samples and specimens for teaching.  Undoubtedly recognizing some potential, he acquired the fossils for the cabinet.

DSC_0083

Benjamin Silliman was about to start a career as a lawyer when he was approached with an offer of professorship in chemistry and natural history.  The only difficulty was that Silliman had no training in science!  But the young man met the challenge with intelligence and energy, and within a few years, delivered the first lecture on science ever given at Yale.  As a respected geologist, teacher, and liberal-minded reformer, Silliman became an influential figure in 19th century intellectual life.  Here, he has inked his own initials, “B.S.”, on the back of this specimen. Image credit: Yale Peabody Museum / Curious Sengi.

Over the years, the natural history collection at Yale grew in size and matured in ambition.  It was time for the university to have a proper museum for the benefit of both its students and the public.  Sensing that the rich, newly-discovered fossil beds of the American West would soon overwhelm the current facilities, Silliman made some initial overtures to wealthy philanthropist George Peabody.  The request seems to have fallen flat; however, it was Silliman’s student, O.C. Marsh, who was finally able to prevail.  By the time Marsh secured a $150,000 gift for what would become the Yale Peabody Museum in 1866, Silliman had been dead for two years.  But it was Silliman’s cabinet that formed the core of the museum collections, including those curious white bones embedded in red Connecticut sandstone which would be the first specimen to enter a newly formed Division of Vertebrate Paleontology.  From an early American teaching collection arose a modern museum with over 13 million specimens — yet another great rise from a small beginning.

 

Special thanks to Dan Brinkman for his assistance in researching this post.

Come see an exhibit celebrating the history of the Yale Peabody Museum and its treasures from 2 April 2016 until 8 January 2017.

 

References

Delair, Justin B. & W.A.S. Sarjeant.  2002.  “The earliest discoveries of dinosaurs:  the records re-examined.”  Proceedings of the Geologists’ Association 113:  185 – 197.

Galton, Peter M.  2012.  “Comment on Anchisaurus Marsh, 1885 (Dinosauria, Sauropodomorpha): proposed conservation of usage by designation of a neotype for its type species Megadactylus polyzelus Hitchcock, 1865.”  Bulletin of Zoological Nomenclature 69 (3): 229-231.

Hall, John.  1821.  “Fossil Bones found in East-Windsor, Connecticut.”  The American Journal of Science and Arts 1 (III):  247.

Hanrahan, Brendan.  2004.  Great Day Trips in the Connecticut Valley of the Dinosaurs.  Perry Heights Press.

Remington, Jeanne E.  1977.  “Curatorial Staff and Other Scientists Associated with the Peabody Museum of Natural History and Its Antecedent Collections, 1802 – 1977.”  Discovery 12 (3):  31 – 42.

Smith, Nathan.  1820.  “Fossil Bones found in red sand stone.”  The American Journal of Science and Arts 1 (II):  146 – 147.

Wyman, Jeffries.  1855.  “Notice of Fossil Bones from the Red Sandstone of the Connecticut River Valley.”  The American Journal of Science and Arts 2 (XX):  394 – 397.

Yates, Adam M.  2010.  “A Revision of the Problematic Sauropodomorph Dinosaurs from Manchester, Connecticut and the Status of Anchisaurus Marsh.”  Palaeontology 53 (4):  739 – 752.

Welcome to the Curious Sengi!

What is that thing?!?

15195028587_cf3173fde2_o

Macroscelides proboscideus, the short-eared elephant shrew.  Image credit:  “Elephant shrew : )” by Black Zack is licensed under CC BY 2.0.

 

The sengi is known by many names:

  • elephant shrew
  • jumping shrew
  • Rüsselspringer (German)
  • Elefantenspitzmaus (German)
  • Slurfhondjes (Dutch)
  • rat à trompe (French)
  • hanejinezumi (Japanese) 

This strange little creature defied description for generations of naturalists and scientists.  Despite all the attention common names give to its wonderful wiggly snoot, these animals are scientifically termed “Macroscelidea,” which means “large thigh.”  While this is certainly true for these active runners, it does seem rather rude to point this out when there are more charming, distinctive features available.

Over the years, the sengi has been variously classified alongside lagomorphs (rabbits and their kin), ungulates (hoofed mammals), scandentia (tree shrews), primates, and, of course, insectivores such as shrews and moles.  In 1998, a study based on molecular data revealed an astonishing relationship:  sengis share the family tree with tenrecs, aardvarks, golden moles, sirenians, hyrax, and. . . . elephants.

In a weirdly prophetic way, we found that elephant shrews are more closely related to elephants than they are to shrews!

Slide1.JPG

An unlikely family reunion.  Clockwise from top left:  African elephant (Loxodonta africana), golden-rumped sengi (Rhynchocyon chrysopygus), streaked tenrec (Hemicentetes nigriceps), dugong (Dugong dugon), Eastern tree hyrax (Dendrohyrax validus), and aardvark (Orycteropus afer).  Image credit:  Jonathan Kingdon via Hedges 2001.

This oddball assortment of mammals — now known as the superorder Afrotheria — is tied together by shared descent from a common ancestor in Africa dating back to at least the mid-Cretaceous period, approximately 100 million years ago.

While the molecular evidence supporting this relationship is robust, a coherent morphological narrative showing the evolution of this group of animals is still unknown.  What explains the presence of long, flexible noses in elephants and elephant shrews?  How is it possible for a related group of animals to generate both a tiny, blind, desert digger like the golden mole and over a thousand pounds of purely aquatic manatee?  The evidence for this amazing history is out there, in undiscovered fossils still encased in African rocks and in the bodies of the living animals themselves.  Nature is filled with such wonders and enigmas, if we only have the patience to uncover these stories.

This is an invitation to dig around and look closer. . .

 

References

Hedges, S.B.  2001.  “Afrotheria:  Plate Tectonics Meets Genomics.”  Proceedings of the National Academy of Sciences 98 (1):  1 – 2.  doi: 10.1073/pnas.98.1.1

Rathbun, G.S.  “Sengis.”  The Princeton Encyclopedia of Mammals.  Ed. D.W. Macdonald.  Princeton University Press.  76 – 81.

Stanhope, M.J. et al.  1998.  “Molecular Evidence for Multiple Origins of Insectivora and for a New Order of Endemic African Insectivore Mammals.”  Proceedings of the National Academy of Sciences 95 (17):  9967 – 9972.  doi: 10.1073/pnas.95.17.9967