Last November we saw these Pygmy Marmosets in Putomayo, a department in south-west Colombia. We flew to Villagarzon from Bogota, staying at the Portal del Sol, an ecolodge owned by a family rewilding the farmland which runs down to the river. And it was by the river that the troop of marmosets appeared. We had already seen the holes they had gnawed in the trees and which they visit to gather the material the tree has extruded.
The shape of their lower incisors is a clear adaptation to gnawing holes in trees. The exudate the marmosets eat is said to be mainly gum rather than sap and to comprise their main source of carbohydrates. Fruit, flowers, buds and nectar also feature in their diet. For protein they catch insects and other small invertebrates as well as small lizards which they search for in the vegetation.
Pygmy marmosets inhabit forests along rivers, spending a great deal of their time gnawing the holes in trees, exhausting it and then moving on.
Both troops had a couple of young. Only one female in the small troop breeds.
These Pygmy Marmosets were of the species originally named and when only one was recognised. Cebuella pygmaea. Those south of two large rivers were considered a subspecies. But the splitters rife in mammalian taxonomy who ignore the biological species concept erected it as a separate species. Cebuella niviventris. To confuse matters further the one we saw has two common names: Northern or Western Pygmy Marmoset as does the other: Southern or Eastern. Taken as a whole or, if you will have it that way, as the two species together Pygmy Marmosets occur in amazonian Brazil, Ecuador, Peru and Colombia. In Colombia it only occurs in the extreme south of the country.
Both groups we saw were low in the trees and made no attempt to flee. They did though carefully inspect us as we did them.
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| Holes gnaws in trees |
Lots more monkeys from Colombia to come.
In 1901, a book appeared which is still worth reading or simply for looking up what was known at the time. It is remarkable because the author was not known for his research on reptiles and amphibians but for birds in particular and vertebrates in general. He was Hans Gadow who was born in Prussia in 1855. After working with the big names in German zoology, he arrived in London to take a job at the Natural History Museum. From there he moved to Cambridge as Curator of Birds in the university’s zoology museum but after two years he was also appointed Lecturer in Vertebrate Morphology at which time he became a naturalised British subject. He was elected to the Royal Society in 1892 but the weird world of Cambridge only promoted him to a Readership in 1920, only eight years before he died.
Gadow's biographer for the Royal Society, David Meredith Seares Watson FRS (1886 –1973) palaeontologist and professor of zoology in University College London wrote:
…and he was greatly interested in the problems of animal colour and of geographical distribution.
In order to have first-hand knowledge of these matters, he travelled extensively in Spain and Mexico, observing amphibians, reptiles, and birds in their natural environments. The results are recorded in two books of travel, and in many papers.
In some ways, the best and certainly the most characteristic work which Gadow published was the volume on Amphibia and Reptiles in the ‘Cambridge Natural History.’ In this book, morphology holds a subordinate place, the greater part of it consisting of short and often most entertaining accounts of individual species regarded as animals living in the world.
It is full of observations of habits of all kinds—food preferences and the capture of food, locomotion, breeding habits, colour changes, the musical appreciation of Tortoises—many of them original, and most confirmed by his own observations of animals which he kept in his house outside Cambridge. Indeed, the whole book well displays the real love and understanding he had of these beasts.
The success of Gadow’s book which appeared in 1901 can also be attributed to the illustrations. Gadow in the preface explained:
The drawings on wood were, with few exceptions, made by Miss M.E. Durham, mostly from living specimens—a procedure which has to a great extent determined the selection of the illustrations.
Why Edith Durham got the commission for illustrating Gadow’s book I do not know, other than, of course, her undoubted talent in drawing living animals that looked like living animals. Her father was a well-connected London surgeon. She was the first of nine children, a number of whom became well known in fields from science from suffragism.
A reminder that if you are reading this article other than on 'Zoology Jottings' it has been stolen from me.
Having used one of Miss Durham’s drawings of Tuataras to illustrate an article, I wondered what else she had produced and was surprised to discover that she had become famous in another field entirely.
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| Edith Durham |
Dubbed the ‘Queen of the Highlanders’ Edith Durham is still celebrated as a national heroine in Albania.
An interesting paper has appeared that shows that a gene present in most vertebrates is absent in snakes. The gene is responsible for the production of the unpronounceable peptide ghrelin. Discovered in 1999, ghrelin is produced by a number of organs in the body and has a multitude of actions, sometimes acting as a true hormone via circulation in the blood and sometimes, it would seem, locally on cells in close proximity. The main source of ghrelin is the lining of the stomach and a major target for its action is the brain.
There are a lots of hormones acting within the body that have an effect on such physiological processes as appetite, satiety, metabolism and gut motility. There is what is perhaps best described as a control network rather than simple cause and effect pathways. There is clearly a great deal of redundancy in the sense of safety-net measures, parallel signalling, cross-talk and feedback that ensure a chemical signal gets through to its intended target, enable effects to come into play in response to changes in food intake, reproductive state etc, and for key variables, like blood glucose concentration to be regulated. One agent of this control network is Glucagon-like Peptide 1 (GLP-1), with which the obese and those who think they are obese are stuffing themselves, is one of those agents. Ghrelin is another. Ghrelin has been called the ‘hunger hormone’ because it promotes the desire to eat when injected. It also seems to have effects on the gut associated with food intake, on glucose metabolism as well as other functions in the brain like learning and memory. It also stimulates the storage of fat.
The authors of the paper pin the reason for the absence of ghrelin in snakes to their ability to go for very long periods without food. Although some snakes may lack that ability, the argument is still valid since the ancestors of snakes may have found selective advantage—or at least found no disadvantage from—a mutation that obliterated the ability to produce ghrelin. Thus it can be argued that all snakes, even those that can, do, or must, eat regularly inherited the condition from a common ancestor.
However, interpretation along those lines gets more complicated because the authors found the gene for ghrelin to be absent in the four species of chameleon examined and in two species of agama. In other words, the loss of ghrelin has happened independently at least three times in the snake-lizard lineage. The authors suggest that chameleons and the particular agamas (two species of Phrynocephalus) have similar lifestyles to the snakes as ‘sit-and-wait’ predators. That may be so but the chameleons do not sit and wait for that long, as anybody who has kept, bred and reared chameleons knows. Therefore, I am not convinced that the loss of ghrelin in particular lizards is necessarily connected with the ability to go without food for long periods.
In a similar vein, members of other groups that go without food for long periods do not lack ghrelin, the crocodilians coming immediately to mind.
A reminder that if you are reading this article other than on ‘Zoology Jottings’ it has been stolen.
Defining with any degree of certainty what ghrelin does in mammals also seems problematic. Mice in which the gene for ghrelin has been knocked out seem to get along fine with only seemingly minor physiological changes, sometimes in unexpected ways. The general view seems to be that in terms of appetite control, for example, it is part of a signalling pathway with a great deal of redundancy.
Ascribing presumed function to biologically active substances found in extant animals to what may have happened in evolutionary history falls into the category of a ‘just-so story’ after Rudyard Kipling’s book of children’s stories including such gems as ‘How the leopard got its spots’. In living animals I have long railed against assumptions that biologically active substances found in milk have a particular or, indeed, any function in the infant, and have suggested the evidence that must be obtained to test each hypothetical function. When applied to evolutionary matters the task is even more difficult or impossible. Fossils, infuriatingly, are not amenable to experiment.
I would argue that it is a pity the authors of the paper on the absence of ghrelin in snakes have written their account almost as a test of the hypothesis that the phenomenon can be explained by the ability to go without food for long periods. Other just-so stories could be plausible: the short alimentary canal with long transit times for digesta, with all that implies for digestion, absorption of nutrients, and gut motility, could be another. Or was loss of ghrelin in their early evolution of no selective consequence to snakes and chameleons; in other words just neutral?
Studies in comparative molecular endocrinology are extremely valuable in stimulating the sort of questions that need to be answered in extant snakes. In short, is the rest of the control network similar to that of other vertebrates, minus grhelin,
‘My conclusion on the story at present: ‘Just so’ but not ‘quite so’.
Pinto RR, Ruivo R, Stiller J, Oliveira D, Castro LFC, da Fonseca RR. 2026. Ghrelin and MBOAT4 are lost in Serpentes. Open Biology. 16: 250162.
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| ‘Sit-and-wait’ is the name of the game for these Common Boas (Boa constrictor) on Cayos Grande, one of the islets of the Cayos Cochinos archipelago off the Caribbean coast of Honduras. They lie on the branches waiting for a bird to land within striking distance since there are no mammals on the island. Our guess was that they were most likely to get the chance of a feed during the migration of large numbers of birds from and to North America. In the shade the boas are difficult for the untrained eye to spot. Once you eye is ‘in’ they are easy to spot in the undergrowth behind the beach. Their coloration is distinctive compared to those on the mainland and the pinkish hue gives rise to their local name of ‘pink’ boa. And if you are staying for lunch the fish and chips are excellent. |
AJP saw this minivet while having a 6-hour walk in the New Territories of Hong Kong last month ‘from Tai Po Kau Nature Reserve up to Leadmine Pass, up to Grassy Hill, then along and up to Needle Hill and down down down to Shing Mun Reservoir’.
On a clear day in Hong Kong minivets are a stunning sight. This one is a male Grey-chinned or Grey-throated Minivet, Pericrocotus solaris. The female is yellow. The scientific name is remarkable since it has not been changed since its description by Edward Blyth in 1846. It is now regarded as a locally common resident with numbers perhaps increased in winter. In Geoffrey Herklots’s time in Hong Kong, the 1930s and 40s, it was marked down as a ‘vagrant’ with very few records. Even in the 1950s and 60s sightings were unusual; two in 1957 and two in 1960.
Although there are a lot more—an enormous lot more—birdwatchers in Hong Kong now than there were in the 20th century, there seems little doubt that the population of this species has increased dramatically. It occurs from the Himalayas eastwards as far as Taiwan and southwards to northern south-east Asia. In much of its range it lives in montane forest.
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| Reg Lanworn |
The trip in 1935/6 was more ambitious in scope, with zoological exploration as a further objective, for which amateur zoologists Anthony and Alvi[l]da Chaplin were responsible, assisted by Keeper Reg Lanworn of the reptile house at London Zoo who took Komodo dragons back to London with him.
However, here I think he is mistaken. The Komodo Dragons were collected on the 1934-35 trip, not the 1935-36 one.
This cutting on Keeper Lanworn’s exploits is from Reynolds News, a now defunct Sunday newspaper owned by the Co-operative Party, of 26 April 1936:
The list of animals received at the Zoo, the gift of course of Lord Moyne, is shown in the Annual Report for 1936: 1 Matschie's Tree Kangaroo, 1 Australian Crane, 7 Keeled Papuan Boas, 7 Fierce Papuan Boas, 5 Common Asiatic Toads, 1 Indian Bull Frog, 3 Greater Indian Rat Snakes, 3 Death Adders, 1 Nicobar Pit Viper, 2 Brown-spottedPit Vipers, 6 Amethystine Pythons, 6 Papuan Cat Snakes, 2 Bocourt's Water Snakes, 2 Broad-headed Water Snakes, 2 Indian Cobras, 1 Indian Python, 1 Moon Snake, 1 Estuarine Crocodile, 1 Parachute Gecko, 1 Peron's House Gecko, 1 Lace Monitor, 4 Helmed Lizards, 4 Fin-tailed Lizards, 8 Indian Monitors, 2 Two-banded Monitors, 5 Great House Geckos, 1 Banded Soft-shelled Terrapin, 4 Ceylon Terrapins, 5 Amboina Box Tortoises, 2 Phayre's Tortoises, 4 Siamese Terrapins, 1 Starred Tortoise, 5 White's Tree Frogs.
The 1935-36 trip was not the first time Reg Lanworn had been sent abroad by the Zoo. On 29 March 1930 he sailed from Liverpool on board the Blue Funnel Line’s passenger/cargo ship Teiresias bound for Singapore. He was aged 22 and travelling first class.
The China Express and Telegraph of 3 July 1930 reported why had been to Singapore:
ARRIVALS AT THE ZOO
GIFTS FROM SINGAPORE
Keeper Lanworn has returned to London from Singapore in charge of a large collection of mammals, birds and reptiles for the Zoo. Through Messrs. Alfred Holt and Co., the consignment, which included 99 crates and cages, was conveyed freight-free. The collection is due to Mr. A. St. Alban Smith, managing director of the Seletar Plantations, who persuaded friends to make gifts, superintended the purchases from dealers, and himself obtained and presented most of the reptiles.
The largest animals are a pair of tigers and a bear, the former presented by Mr. and Mrs. A. G. Glenister and the latter by Mrs. Glenister and Mrs, E. L. D. Evans, of Ipoh, Perak. Two young orang-utans, four tree-kangaroos, four crowned pigeons, and two young cassowaries are additions which were very much wished for. The assortment of reptiles is a very fine one.
The list of animals in this shipment donated by Alfred St. Alban Smith (1880-1940) takes more than a whole page in the Annual Report for 1930. The reptile collection was indeed a fine one and Smith, a rubber planter in Johore who also sent collections of reptiles to zoos in the USA, was awarded the Society’s silver medal in 1931.
Reg Lanworn, in charge of the 99 crates, had shown that he could be ‘let out’.
Arthur Reginald Lanworn† was born in Kentish Town on 13 March 1908. I do not know when he became a keeper at the Zoo but most likely on or shortly after his leaving school in 1922 (the school-leaving age was 14). Several tragedies can be found in the records of Lanworn’s life. In 1939 his sister and her boyfriend were found dead in a gas-filled room. Her parents had refused consent to their marriage. Sir Bernard Spilsbury, the famous forensic pathologist reported to the also famous coroner, Bentley Purchase, most recently seen portrayed in the film Operation Mincemeat, who recorded a verdict of suicide while of unsound mind. Reg Lanworn appeared as a witness at the inquest and stated ‘it would have been satisfactory to both parties if they had got married. They were very fond of each other’.
Personal tragedy again struck in 1942. Having married in 1933 and with a daughter, his new-born son and his wife died. He married again in 1948. Then, in 1960, tragedy struck the Reptile House. Workmen returned to the Reptile House after Christmas to continue servicing the artesian well which supplied both the Reptile House and the Aquarium via a pit in the floor. On removing the cover a natural accumulation of carbon dioxide gushed forth. The workmen employed by an outside contractor were immediately overcome and fell into the narrow pit. Two keepers trying to rescue the men were also rendered unconscious; one died immediately, the other eleven months later. The first was Lanworn’s Head Keeper, Frederick Dexter, aged 46, who had worked at the Zoo for 32 years. The other was Anthony Hodgson, 22, only recently returned from National Service. Keepers made heroic efforts to save the men earning commendations from the coroner. Ten employees of the Zoo were recognised by the Royal Humane Society for their prompt and gallant efforts in both the rescue and the attempts at resuscitation.
As he rose through the ranks in the Reptile House, Reg Lanworn often found himself in newspaper reports and on the cinema newsreels. Anything to do with snakes or crocodiles is always good for column inches and Keeper Lanworn being bitten by a newly-hatched python was good a story in the Daily Express as was the Common Boa arriving in cargo as a stowaway at London docks not turning out to be the as reported to the Zoo a feared Fer-de-Lance. Two ’22 ft’ pythons made the newspapers in 1949 when they both grabbed a chicken at feeding time and fought tenaciously. Lanworn, then Head Keeper, and Jack Lester, Curator of Reptiles, pulled at either end of the tangle.
A newspaper report quoted in an article by Nick Thompson suggests Reg Lanworn was called up to serve in the forces during the Second World War.
London Zoo like most institutions had a strict hierarchy. Keepers were one class and curators and above were the other. In military terms, keepers were private soldiers and non-commissioned officers; curators were the officers. Keepers could make it up the promotion ladder to reach the pinnacle of Overseer, of which London Zoo had around five. They were the sergeant-majors—and they had a uniform to match their status. Keepers had short jackets but overseers had long coats similar to those worn by the guards regiments in winter. When on public duty, keepers wore their uniforms including summer when they must have broiled. I had a long talk one summer with Reg Lanworn who was keen to move out of the Reptile House to stand by the old reptiliary. His uniform in the heat of the Reptile House in summer must have been rather uncomfortable.
I do not know when he was promoted to Overseer of Reptiles but I have found a record showing him in that grade by 1955.
In the late 1940s and early 1950s the Reptile House had the reputation of being a place friendly to amateur herpetologists as I reported HERE. At that time Jack Lester was curator and Margaret Southwick was also on the staff. Margaret married Reg Bloom, then also employed at Regents Park having been an animal collector withJohn Seago in East Africa, in 1953. The newly married Blooms then left for East Africa before returning to UK where he was involved in starting and/or running a number of zoos. Lester, Lanworn and Southwick were founder or early members of the British Herpetological Society after it was formed in 1947.
Reg Lanworn retired after more than 40 years at the Zoo in 1968, aged 60. By then he was listed as ‘Herpetologist’. I seem to recall he was given that title in recognition of his work and the simple fact that at the time he was the only member of the Zoo staff, apart from his own juniors, who knew anything about reptiles after the death of Jack Lester in 1956. In his new role he must have been sitting on that cusp between ‘keeper’ and ‘curator’. A year earlier he was awarded the Society’s Bronze Medal ‘for outstanding service in the Reptile House’.
After retirement he wrote a popular book on reptiles and was co-author of a series on animal life in different parts of the world.
In retirement Reg and his wife moved out of London, to the village of Barton Mills near Mildenhall in Suffolk, and later into Mildenhall. He died on 29 January 2005, aged 96.
Reg Lanworn served in the Reptile House from the regime of Joan Proctor as Curator of Reptiles, through the periods when Burgess Barnett and Jack Lester were in charge to a time in the 1950s and 60s when he effectively ran the whole show. He also witnessed the periodic upheavals that the Zoological Society still brings upon itself, including the unfortunate removal of Burgess Barnett, the Cansdale affair plus of course the untimely death of Jack Lester. He operated during the period when the London Zoo’s Reptile House, despite its many problems that became more apparent over the years, and the reptile collection was in its heyday. I am pleased to have met him and to recognise the success the Zoo had in taking boys from north London and producing the devoted, highly capable and knowledgable members of staff who stayed at Regents Park until they retired.
Mrs Olive Parton Dutta (1915-1994) was the wife of Reginald Sirdar Mohammed Dutta (1914-1989), a well-known owner of an aquarium shop on Blandford Street, Marylebone. He wrote a number of books on aquaria and fish keeping.
*Anthony Freskyn Charles Hamby Chaplin, 3rd Viscount Chaplin (1906-1981) was Secretary of the Zoological Society of London from 1952 to 1955. He was married to Alvilde Bridges (1909–1994) from 1933 until divorce in 1950.
†At birth he was registered as Arthur Reginald but in other official records he is Reginald Arthur.
Cooper A, Ellis M, Guggisberg CAW, Lanworn R. 1968. Animals of the World. Europe. London: Hamlyn.
Stanley N. 2016. 'Some Friends Came to See Us’: Lord Moyne's 1936 Expedition to the Asmat. London: British Museum ISBN 978 086159 206 7 ISSN 1747 3640.
Wheeler A, Christie D, Cohen E, Jarman C, Lanworn R. 1970. Animals of the World. Europe. London: Hamlyn.
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| Daily Mirror 4 May 1948 |
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| Komodo Dragon on the island of Rinca September 2016 |
Mrs Churchill wrote to Winston about the time spent there:
This has been an enchanting bewildering & exciting week - I meant to keep this letter in the form of a diary adding to it day by day but failed to do it - In this way I could have made you feel the excitement the suspense the heat the repeated disappointments the fearful smell of the decaying baits - (which of course had always to be approached and watched with the wind blowing towards one). Side by side with all this "big game' 'Boys Own Annual' world is the enchantment of this island which is the most beautiful thing I have ever seen & is perhaps one of the loveliest wildest strangest spots in the world. It is deeply indented with bays and lagoons. It has innumerable paradise beaches - some of the finest sand (there is a pink one of powdered coral) some of wild rocks with coral gardens far lovelier than at Nassau, & accessible. That is if you are not afraid of being observed by a giant polyp or tickled by a sea snake 12 foot long.
Three of the lizards captured were selected to take home. They were around 4 feet long. On board, one disappeared, presumed lost overboard, after the carpenter lightened the lids of their crates by adding a wire-netting panel—which proved to be no great barrier to a dragon on the move.
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Rosaura off Cape Brett, New Zealand, photographed by Lady Vera Broughton. From Lord Moyne's book Walkabout: A Journey in the Lands Between the Pacific and Indian Oceans, Heinemann, 1936 |
Winston Churchill sent a car and a lorry to Southampton to collect Clementine from Rosaura after she docked on 30 April 1936. Along with her luggage (by now swollen with souvenirs) there was her pet pigeon from Bali (a Zebra Dove possibly) and. I read, a pair of Black Swans for the Chartwell estate, presumably to add to the ones already there. The Black Swans caused Winston considerable anguish as he tried to protect them from the local foxes. Some of her ethnographic souvenirs were later given to the British Museum.
The Society’s Report for 1935 shows that the two lorries sent by the Zoo a day after Rosaura docked brought back with them: 1 Highland's Long-tailed Tree Mouse, 1 Ceylon Pit Viper, 4 Green Pit Vipers, 3 Brown Spotted Pit Vipers, 9 Helmed Lizards, 1 Indian Changeable Lizard, 3 Fan-footed Geckos, 1 Delande's Gecko, 4 Ceylon Terrapins, 5 Blue-rumped Parrots, 2 Tuatara [then spelt Tuatera as was common at the time], 2 Komodo Dragons, 2 Kagus. In zoo asset terms the last three species were the crown jewels.
What has puzzled me since first reading about this trip is: who looked after the animals on the Rosaura? I still do not know but I suspect it was not an ideal arrangement because on the next trip in 1935-36—as we shall see in the next article—there was an expert on board.
Newspaper recorded the problems of housing Komodo Dragons in wartime. The London Evening News reported in July 1941 that the dragons had an egg each for the first time since eggs were rationed. A visitor to the Zoo provided them. In 1944 the glass was blown out of half their cage in the Reptile House. Permission was granted by the Ministry of Works, which controlled the use of building materials, and the Zoo’s own workmen did the repairs. By contrast, repairs to houses damaged on nearby Prince Albert Road had to wait.
The two—a pair—Komodo Dragons lived until 1946. Accounts differ as to their size when they died: 6 to even 8 or 9 feet according to which newspaper you read, compared with 4 feet on arrival 10 years earlier. The female was recorded of having died from retained necrotic ova, so her size matched her obvious sexual maturity. I wonder if she had access to soft earth in which to lay her eggs?
Soames M. 2002. Clementine Churchill. Revised and updated edition. London: Doubleday.
Stanley N. 2016. 'Some Friends Came to See Us’: Lord Moyne's 1936 Expedition to the Asmat. London: British Museum ISBN 978 086159 206 7 ISSN 1747 3640.
Thompson N. 2022. How London Zoo acquired its second pair of Komodo Dragons. Bartlett Society Journal 30, 19-32.
