Friday 28 February 2020

Chameleons I have kept and chameleons I have seen in the wild

This Jackson's Chameleon was the second chameleon I
kept ca 1960
I was writing something on chameleons for another purpose when I wondered how many species I had kept and how many I had seen in the wild. That thought sent me into old records and trip reports. The first chameleon I kept was the small Two-lined Chameleon, now known as Trioceros bitaeniatus, from East Africa. In the 1950s it was stated that the ‘dwarf’ species lived longer than the larger ones. Quite by chance the way I kept it turned out to be in many ways ideal. Over two winters it lived on a wrought-iron framed mirror in the sitting room, eating flies from hatched fishing-bait maggots and mealworms held in forceps. In summer it was in a vivarium but on some days it was parked in an apple tree, with a piece of meat or fruit hanging by a thread to attract insects. At all times, the temperature fell at night—no central heating then. Later I had a single Jackson’s Chameleon (Trioceros jacksoni) and large number of Von Höhnel’s Chameleon, better known these days as the Helmeted or High-casqued Chameleon, Trioceros hoehnelii.

Natal Midland Dward Chameleon (Bradypodion thamnobates)
The late Bob Davies had a friend (whose name I cannot remember) who
started a colony of these chameleons in UK in the late 1980s.
I had some of the offspring which in turn bred.

Natal Midland Dwarf Chameleon - young
These chameleons bear live young

Natal Midland Dwarf Chameleon - a few days old

For decades attempts at keeping most species of chameleon in captivity for any length of time seemed doomed to failure. Indeed, they were one of the few groups of animals in which longevity was shorter in captivity than in the wild. However, that was only partly true since some species, for their size, do not live that long, some have very short lives, whereas others, the Veiled or Yemen Chameleon (C. calyptratus), for example, which proved to be easy to keep and breed will live for up to 5 (females) to 8 (males) years.

As with many reptiles, once captive-breeding was achieved with many species, subsequent breeding proved easier. The stress of capture, storage and transport was one reason for the lack of success. Better environmental conditions and nutrition also played a large part. I was astounded when I took some faecal samples from wild-caught chameleons in the 1980s. The parasite load was staggering: worms, protozoans and coccidial spores abounded. I could have sold seats by the microscope to those wanting to see a parasite zoo. It is not surprising that chameleons in general proved ‘difficult’ animals.

During the 1980s there was concern that since many species of chameleon survived so poorly in captivity that there would not exist reliable methods of ex-situ conservation should that prove necessary for some Madagascan species where habitat loss has been so dramatic. So many species have now been kept and bred successfully over a number of generations that such a concern has not been realised.

Carpet Chameleon (Furcifer lateralis)
This Madagascan species (sitting on the hand of the late Bob Davies)
is an egg-laying species. We both tried to breed this species but the
eggs were infertile. ca 1991

Flap-necked Chameleon (C. dilepis) ca 1991

Oustalet's Chameleon (Furcifer oustaleti)
Madagascar 2003

As much as I did learn about chameleons (and here I echo a former colleague who argued that if we learn how to keep and breed and animal in captivity then we know an awful lot—not everything but an awful lot—about how that animal works) there is nothing like seeing and observing animals in the wild. From Kenya in 1991, Madagascar (three weeks in 2003 and two days in 2006) and the Republic of Congo in 2014 we saw and watched chameleons in the wild. The fauna of Madagascar is of course amazing and for chameleon aficionado, who can see easily the radiation that has occurred there ranging from the tiny Brookesia to the huge Oustalet’s, one of the great wonders of the natural world.

Spectral Pygmy Chameleon (Rampholeon spectrum)
Republic of Congo 2014

And here are the lists I compiled, firstly of the ones I kept between 1959 and 1994:

Common NameScientific Name
Helmeted ChameleonTrioceros hoehnelii
Two‑lined ChameleonTrioceros bitaeniatus
Elliot's ChameleonTrioceros ellioti
Jackson's ChameleonTrioceros jacksoni
Johnston's ChameleonTrioceros johnstoni
Flap-necked ChameleonChamaeleo dilepis
Senegal ChameleonChamaeleo senegalensis
Carpet ChameleonFurcifer lateralis
Natal Midlands Dwarf ChameleonBradypodion thamnobates

...and secondly, chameleons I have seen in the wild from 1991 onwards:

Common NameScientific NameCountry
Stump-tailed ChameleonBrookesia superciliarisMadagascar
Spectral Pygmy ChameleonRampholeon spectrumRepublic of Congo
Short-horned ChameleonCalumma brevicorneMadagascar
Parson's ChameleonCalumma parsoniMadagascar
Nose-Horned ChameleonCalumma nasutumMadagascar
Malthe ChameleonCalumma maltheMadagascar
Oustalet's ChameleonFurcifer oustaletiMadagascar
Rhinoceros ChameleonFurcifer rhinoceratusMadagascar
Spiny ChameleonFurcifer verrucosusMadagascar
Jewel or Carpet ChameleonFurcifer lateralisMadagascar
Wills's or Canopy ChameleonFurcifer willsiiMadagascar
Panther ChameleonFurcifer pardalisMadagascar
Helmeted ChameleonTrioceros hoehneliiKenya
Flap-necked ChameleonChamaeleo dilepisKenya

Wednesday 19 February 2020

A Hong Kong Sunbird fest

Hong Kong birdwatchers and photographers were out in force to see these 'Occasional Visitors' over Chinese New Year. Our Hong Kong correspondent was there, hiking from Shing Mun over Lead Mine Pass to Tai Po Kau.

Mrs Gould's Sunbirds (Aethopyga gouldiae) was what the birders were there to see. When first seen in Hong Kong they were regarded as escapees from captivity but it is now realised that Hong Kong is part of their natural range (from India, Nepal and Bhutan to Bangladesh, China,  Burma, Thailand, Laos and Viet Nam). First described in 1831 by the lawyer and politician Nicholas Vigors (1785-1840) while Secretary of the Zoological Society and pursuing his misguided 'quinarian system' of classification, it was named for Mrs Elizabeth Gould (née Coxon) (1804-1841) the artist wife of John Gould FRS, ornithologist, taxidermist and artist.

Mrs Gould's Sunbird - male

Mrs Gould's Sunbird - male. To show the iridescent feathers of the head

Feeding on the same flowers were 'Resident' Fork-tailed Sunbirds (Aethopyga christinae). Also called Mrs Swinhoe's Sunbird after the wife, Christina, née Lockie, of Robert Swinhoe FRS (1836-1877) who described the species in 1869, this bird in Hong Kong was regarded as a rarity when we lived in Hong Kong in the 1960s. First seen in Hong Kong in 1959, it could for years only be seen at Tai Po Kau. Since then it has spread throughout Hong Kong and on our first return to Hong Kong in 1997 a pair was nesting yards from our room at Robert Black College at the University of Hong Kong.

Fork-tailed Sunbird - male

Female sunbirds are easily overlooked:

Mrs Gould's Sunbird - female

And here are the photographers:

Also around was this Mountain Bulbul (Ixos mcclellandii) once a great rarity in Hong Kong but now regularly spotted:

Mountain Bulbul

A Verditer Flycatcher (Eumyias thalassinus)

Verditer Flycatcher - male

...and a female Red-flanked Bluetail (Tarsiger cyanurus) showing why it used to be called a bush-robin, a winter visitor to Hong Kong from the north:

Red-flanked Bluetail

Finally, a portrait of Mrs Elizabeth Gould with a pet Cockatiel. As well as illustrating John Gould's publication she had eight children, dying at the age of 39 after the birth of the eighth.

Sunday 16 February 2020

Bouin’s fluid. But who was Bouin?

Bouin’s fluid will always be etched on my brain for a then commonplace but, with hindsight, foollhardy incident. During my final year at school I was a part-time laboratory steward (pay £2.14 shillings per week). One of my first jobs was to sort out the shelves at the back of the Advanced Biology Lab (now, along with the entire school, demolished). There was a 500 ml bottle half-full of Bouin’s fluid. The problem was that it had a ground-glass stopper. Even I knew that picric acid was an explosive and that anything containing picric acid should never come into contact with metal, must be kept dry and never put in anything with a ground-glass stopper. Friction or a sharp tap could detonate the dry material in the neck. I tried gently to remove the stopper. It was stuck. I had the wit not to try tapping the stopper on a bench to shift it because I could see dried picric acid in the neck. I then tried gentle heat from water heated with a bunsen burner (no piped hot water supply then) around the bottle. I grasped the stopper—there were no goggles or any other bits of safety equipment in the whole school—and pulled, without twisting. Out it came, but I don’t think I imagined hearing a small but definite ‘crack’. I now read that such episodes have to be dealt with by the bomb-disposal squad. I moved on to the next bottle. It was picric acid, obviously used in the past for the Bouin’s fluid. The contents were wet and it did have a rubber stopper.

Bouin's Fluid is available
In the early and middle decades of the 20th century, the microscope was THE research tool in zoology—and many other -ology—laboratories. With the microscope came the paraphernalia to cut sections and stain the once-living material so that the various structures could be seen. Shelves in universities and schools were filled by a vast array of bottles containing various tissue fixatives, used to prevent shrinkage and decomposition, embedding materials, dyes, clearing agents, and mounting media for the thin sections. There was usually the evocative smell of Canada Balsam and xylol (then called xylene). Many of the mixtures of chemicals and dyes were named after the person who first used and described them during the golden age of histology. The obscure names on the faded labels of dusty bottles on equally dusty dark-stained wooden shelves added to the impression of alchemy rather than cutting-edge science.

Some of those named reagents have stood the test of time, while others have fallen by the wayside. The fixative of choice for the commonest staining method for mammalian tissues was and still is Bouin’s Fluid, a mixture of formaldehyde, acetic acid and picric acid. Having been aware of that fixative since the late 1950s, I had no idea who Bouin of his eponymous fluid was. Until last week that is when I saw a photograph taken at the First International Conference on Sex Hormones held in Paris in 1936. All of those present were well-known endocrinologists and I spotted those knew well, had met* or had heard of. And there was a Professor Pol Bouin of Strasbourg. Was he, I wondered, the Bouin of Bouin’s Fluid?

Pol Bouin circled
From Zuckerman's biography, From Apes to Warlords

Indeed he was. A bit of digging on Google soon turned up a biography. Pol André Bouin was born in Vendresse in northern France in 1870. While still a medical student in Nancy he became interested in morphology and was appointed preparateur d’histologie. He published the recipe of his new fixative in the same year that he qualified in medicine, 1897.

Pol Bouin
from Parkes
Bouin's rise in French science was meteoric, first in Nancy and then, after the First World War, in Strasbourg. His research covered a wide range of tissues and sub-cellular structures but he came to specialise in the reproductive organs and his fixative was devised for a study on seminiferous tubules. Much of his research and that of his collaborators in Strasbourg demonstrated the presence of putative hormones but preceded isolation and identification of the hormones themselves, prolactin and progesterone, for example. Similarly, his research in cytology, on the ergastoplasm (now the endoplasmic reticulum) was completely superseded once the electron microscope came on the scene.

Sir Alan Parkes—also on that photograph in Paris in 1936—wrote an obituary in Journal of Reproduction and Fertility. He began:

Pol Bouin, one of the pioneers of modern biology, and especially of the histological approach to physiological problems, died on February 5th, 1962, at the age of 92 at his family home in the Ardennes, to which he had retired finally in 1946. More than 20 years have elapsed since Bouin left active scientific work and time may have dimmed the bright light of his achievements for some of the younger generation. But in his own country, especially to his associates there, to the older generation elsewhere and to all with a sense of scientific history, Bouin ranks with F. H. A. Marshall and Ludwig Fraenkel as one of the small group of research workers who at the beginning of this century laid the foundations of our modern knowledge of the reproductive processes. Possibly even more significant than his personal original work was the influence he exerted directly and through his pupils. It may truly be said that Bouin founded a scientific dynasty which provided and continues to provide the major part of the great French contribution to our knowledge of the physiology of reproduction. 

But Parkes made no mention at all of Bouin’s fluid!

*Solly Zuckerman, Ruth Deanesly, Alan Parkes, Idwal Rowlands, Frank Young

Bouin first reported the use of his fixative in this paper:

Etude sur l'évolution normale et l'involution du tube seminifere. I. Modifications régressives du processus spermatogénétique provoquées expérimentalement. II. Phénomènes cytologiques anormaux dans l'histogenèse et l'atrophie expérimentale du tube seminifere. Arch. Anat. micr. 1, 225-265. 1897

Ortiz-Hidalgo C. 1992. Pol André Bouin, MD (1870-1962). Bouin’s fixative and other contributions to medicine. Archives of Pathology and Laboratory Medicine 116, 882-884.

Parkes AS. 1963. Pol Bouin 1870-1962. A memoir. Journal of Reproduction and Fertility 5, 301-307.

Monday 10 February 2020

A Hong Kong Spider

Walking the hills last weekend, our Hong Kong correspondent spotted this large spider in a drainage ditch. We do not have a book on Hong Kong spiders but it looks like the huntsman, Heteropoda venatoria which goes by a number of common names including Giant Crab Spider. Huntsman spiders are straight killers, building no web to trap their prey. The venom contains a potassium channel-blocker—bad news for anything with a nervous system. Insects are its main prey but it has, apparently, also been known to kill scorpions and bats.

Saturday 8 February 2020

Joan Procter and Sir Peter Chalmers Mitchell at London Zoo in the 1920s-30s: A Dissenting Account from Solly Zuckerman

Solly Zuckerman with
monkey. Oxford, 1935
Apes to Warlords
I have written several times about Joan Procter, Curator of Reptiles at London Zoo until her death at the age of 34 in 1931, and her relationship with her boss, Sir Peter Chalmers Mitchell.

All the accounts of Joan Procter’s life and achievements were written by Chalmers Mitchell, that great self-publicist, and it is difficult to assess how others viewed her. All present-day accounts are derived from Mitchell’s various publications but I knew that sometime in the past I had come across a dissenting view. Finally, I remembered that Solly Zuckerman in the first part of his autobiography published in 1978, was the dissenter. Zuckerman, before his meteoric rise to power in British science and a life peerage, had been employed by the Zoological Society of London in 1928-1932 as Prosector—research anatomist in modern parlance—to work on the remains of the animals that died in the Zoo. As well as doing this he built on earlier research he had done in South Africa and wrote his famous book, The Social Life of Monkeys and Apes. He later became one of Chalmers Mitchell’s successors as Secretary of the Zoological Society.

This is what Zuckerman had to say on Chalmers Mitchell and Joan Procter:

Joan Procter
The main executive officer of the governing body, which is an elected and unpaid Council, is the Secretary. Sir Peter Chalmers Mitchell, who occupied that office during the five years when I was a member of the Society’s staff, was not only the Society’s un­questioned ruler, but also a well-known character in the life of London. In his time the secretaryship was a highly paid full-time post, which enjoyed a number of privileges, including a luxurious flat on the upper floor of the Society’s main office. Mitchell ruled his domain with a rod of iron, and while his chief administrator was Dr. Vevers*, he himself seemed to be ruled by Joan Proctor, the Curator of Reptiles, a young woman of powerful personality. Once I was commanded to go to see her in her house near the Zoo. This was an unnerving experience, since she kept as a pet a wild Serval cat, on which I had to keep a wary eye as she spoke. She ordered me to relieve some giant tortoises of the constipation from which she supposed them to be suffering. I did not have the slightest idea what to do but, in my anxiety to get away, said that I would attend to the matter. Later that day I joked about my impending task with Malcolm Pearson, a medical student friend. Malcolm had a nice sense of humour, and after we had discussed the matter, I sent a message to Joan Proctor’s staff to have the affected animals strung up in tennis nets by 9 o’clock the next morning, and to have pails of soapy water and syringes prepared for a visit which I and another doctor would be making. There was no need for any enemas by the time we arrived. Excitement alone had done the trick, and the centre of the new Reptile House was a terrible mess. Apart from asking me to give anti-venom serum to a keeper who had got himself bitten by a snake, Joan Proctor never bothered me again. Malcolm and I dined out more than once on the story.
Peter Chalmers Mitchell
Chalmers Mitchell was not the only member of the Society’s Council who had fallen under Joan Proctor’s spell, and when she died in 1931 at the early age of 34, a medal, one side of which bore her likeness, was struck in her honour. The intention was that it should be presented each year to a distinguished expert on reptiles, but I can find no record that it was ever awarded. Perhaps she was not sufficiently outstanding scientifically to be commemorated in this way. The one copy of the medal that I know still exists is among the Society’s memorabilia. 

I think we can take it that Zuckerman was not overly impressed by Miss Procter. Read my earlier article Joan Procter and Sir Peter Chalmers Mitchell. Scandalous Rumours at London Zoo and Whipsnade in the 1920s and try to decide if Zuckerman’s account helps us decipher what was going on.

*Geoffrey Marr Vevers (1890-1970). Not to be confused with his son, Henry Gwynne Vevers (1916-1988).

Mitchell PC. 1929. Centenary History of the Zoological Society of London. London: Zoological Society of London

Zuckerman S. 1978. From Apes to Warlords. London: Hamish Hamilton

Thursday 6 February 2020

Doflein’s Salamander

Some salamanders are very strange beasts. None more so than the tropical Central American species in the genus Bolitoglossa. They can shoot their tongues to catch prey like a chameleon, they can shed their tail when threatened just like many lizards, and they breed entirely on land. They belong to the group of salamanders—the Plethodontidae—that have no lungs, relying on gaseous exchange through the skin. The bolitoglossines are sometimes called climbing salamanders because they can and do live in trees and shrubs, a fact difficult to accept when seeing one for the first time since they not only have webbed feet but appear stiff and ungainly. But the fleshy, webbed feet are deceptive. When planted on a leaf and arched they act as suction cups.

I was barely aware of the existence of these salamanders in the years I first became interested in reptiles and amphibians. They do not get a mention in the popular books available in the 1950s and 60s in Britain that were written by Doris M Cochran or Robert Mertens.

About 30 years ago, I was given a few to keep by whom I cannot remember and my records have disappeared. Individuals of one species were beginning to appear on animal dealers’ lists. That species was Bolitoglossa dofleini from Guatemala, Honduras and Belize. At the time there was no commonly used name. Now IUCN list the following: Alta Verapaz Salamander, Doflein's Mushroomtongue Salamander, Doflein's Salamander, Palm Salamander. It was first described and named by Franz Werner (1867-1939) after Franz Theodor Doflein (1873-1924) who collected the salamander on an expedition to Central America in 1898.

Doflein's Salamander
One of the ones I tried to keep 30 years ago


Only years later did I learn that my experience of trying to keep this species was the same as everybody else’s. They appeared to live and feed perfectly well but after a few weeks or months they became lethargic, shed their tails and died. I was annoyed and puzzled that I was unable to keep animals that initially had appeared fit and healthy. Had I got something wrong or did they have some disease that developed with time?

In 2004 a note appeared in Veterinary Record. The authors made the general observation that B. dofleini ‘is generally considered notoriously difficult to keep alive; most imported animals do not survive beyond the first two months after importation’. Three males and two females, recently imported into Belgium, became anorexic and apathetic over a one- to two-week period. Then the hands and feet appeared slightly swollen and began to point upwards. Finally, the tail was shed and the salamanders died 2 to 10 days later.

At this time there was growing realisation that the chytrid fungus, Batrachochytrium dendrobatidis, was having devastating effects on amphibian species throughout the world. The authors of the paper found large numbers of chytrid cells in the cornified layer of the skin all over the body. The origin of the infection could not be determined because the salamanders could have been in contact with other animals in transit to Europe or in the dealer’s premises from which they were obtained.

The suggestion the authors made was that proliferation of the chytrid in the skin might have compromised gaseous exchange in these lungless amphibians. Kidney damage in the form of hyaline droplets was also present but whether this was related to the presence of chytrid was not known. A strange finding in three of the animals was the impaction of the stomach with moss and wooden particles.

I remained puzzled after reading the report in Veterinary Record. While clearly demonstrating the presence of chytridiomycosis, I really could not decide if the animals had died OF or WITH the disease.

Around 1990 the only information I could find indicated that Doflein’s Salamander was found in lowland rainforest. I therefore kept them at temperatures appropriate to that low altitude in Central America. However, I began to wonder if the temperature was too high. Later publications showed an altitude range of 50-1500 metres in the wild including premontane to lower montane wet forest. I did not know where the ones I was given had been collected but if they were from, say, an altitude of 1000 metres, I should have tried keeping them 10°C below that of my simulated lowland tropical environment. I have found suggestions in online fora that people attempting to keep and breed these fascinating amphibians had also tried too high a temperature. In this respect, I read there has been controversy in the past over the altitudinal distribution of the largest of the bolitoglossine salamanders, e.g. B. dofleini, that rely on oxygen uptake through the skin. One view was that large lungless salamanders can only occur at relatively high altitude because the oxygen requirements of the tissues at the higher temperatures of lower altitudes cannot be supplied by the relatively small surface area of the skin. Others have contested that view. However, cutaneous oxygen uptake compromised by the presence of chytrid together with a high environmental temperature in captivity might just have created the perfect patho-physiological storm. 

I discovered that from their size the salamanders given to me must all have been females; males are much smaller. Collectors apparently searched the leaf litter and because the females tend to live there while the males prefer to clamber in the trees and bushes it was mostly females that were imported into Europe.

The only success at keeping B. dofleini I have come across is at Fort Worth Zoo. It was reported in 2012 that ten (all females) had been kept for 6 years. On arrival, all had been treated for chytridiomycosis. I have not seen any reference to the environmental temperature in their exhibit. I have been unable to find in the various papers, whether or not those exported for research have been kept successfully for any length of time.

Fortunately, no licences are now issued for the collection of any species of Bolitoglossa (which occur in Central and the north of South America). B. dofleini takes 10-12 years to reach sexual maturity. Thus a breeding population could, by uncontrolled collection of adults, be reduced to dangerously low levels very quickly. IUCN classify the species as Near Threatened.

It does, though, concern me that nobody has a method for breeding any species of Bolitoglossa in captivity—or at least if they have, nothing seems to have been published. The radiation in these salamanders has been so great that they represent 40% of all the tailed amphibians of the world. If—perish the thought—a captive-breeding programme became necessary to ‘lifeboat’ a conservationally important species, there would be very little background knowledge with which to start.

The only consolation of my experience with Herr Doflein’s Salamander was that I did get to see but not to record the remarkable tongue in action. It can be projected up to 31% of body-length in that species in under 20 milliseconds. The maximum velocity achieved was 7 metres per second and  the maximum acceleration 4500 metres per second per second. In other words the sticky tongue hits the prey at a speed of 25 km per hour, less than 0.02 seconds after launch. The performance of the paired tongue projector muscles ‘exceeds the greatest maximum instantaneous power output of vertebrate muscle by more than an order of magnitude’. 

Here is the video made by Stephen Deban, one of the authors of the paper on the high-power tongue projection in another species of Bolitoglossa, B. franklini:

Deban SM, O’Reilly JC, Dicke U, van Leeuwen JL. 2007. Extremely high-power tongue projection in plethodontid salamanders. Journal of Experimental Biology 210, 655-667. doi:10.1242/jeb.02664 

Feder ME, Papenfuss TJ, Wake DB. 1982. Body size and elevation in neotropical salamanders. Copeia 1982, 186-188.

Pasmans F, Zwart P, Hyatt AD. 2004. Chytridiomycosis in the CentraI American bolitoglossine salamander (Bolitoglossus [sic] dofleini). Veterinary Record 153, 153.

Scales JA, O’Donnell MK, Deban SM. 2017. Thermal sensitivity of motor control of muscle-powered versus elastically powered tongue projection in salamanders. Journal of Experimental Biology 220, 938-951. doi:10.1242/jeb.145896 

Wake DB, Dresner IG. 1967. Functional morphology and evolution of tail autotomy in salamanders, Journal of Morphology 122, 265-306.

Sunday 2 February 2020

Clifford Emmens: Aquarist, Endocrinologist and the Natural History of Bombing

Clifford Walter Emmens
(from Biographical Memoir, AAS)
To anybody keeping and breeding tropical fish from the 1950s until the 1990s, the name C.W. Emmens would have been familiar as the author of a number of the better books on the subject. Few amateur aquarists would have realised that Emmens was professor of veterinary physiology in the University of Sydney and even fewer that he had an important rôle in one of the key developments of the Second World War.

Clifford Walter Emmens (1913-1999) was a member of Solly (later Lord) Zuckerman’s famous Oxford unit studying the effect of bombing on the civilian population. From studies on damage to industrial effectiveness and civilian morale after German attacks on British cities, Zuckerman and his team turned their conclusions around to consider what Allied attacks on German cities would achieve. The conclusion—very little—was anathema to the 'Air Barons' in the Royal Air Force and U.S. Army Air Force (the latter being desperate to become independent of the army) who had convinced themselves as well as powerful figures in and around Winston Churchill that Germany could be brought to submission by ‘strategic’, in other words, area-bombing. The story is now well known even though Zuckerman exposed later attempts to whitewash the failings of the senior officers of Bomber Command in reports and official histories. Throughout of course there had been the snide comments of the ‘what do a bunch of biologists think they can tell us about air warfare’ type, a view even promulgated by Churchill’s personal friend and scientific adviser, the physicist, Frederick Lindemann, Lord Cherwell, who was a firm believer in strategic bombing—an example of the many things he got completely wrong.

Emmen’s job in Zuckerman’s unit and how be escaped the National Institute of Medical Research in order to take a more active rôle in the war effort is told in his biographical memoir for the Australian Academy of Science and by Zuckerman in the first part of his autobiography.

After tackling the problem of assessing the effect of bombing on the civilian population in Germany, Emmens joined Zuckerman and other members of the unit for bombing surveys after the invasion of Sicily. This detailed work informed the bombing plans for the run-up to the D-Day landings in June 1944. Those plans resulted in the now well-known confrontations with ‘Bomber’ Harris and his acolytes of Bomber Command—and with Lindemann—on using the heavy bombers to destroy rail communication hubs and their associated repair shops, rather than for attacking the ‘strategic’ targets by area-bombing German cities which Harris et al. believed would lead to the capitulation of the enemy. Zuckerman’s prediction based on results of the bombing surveys that such disruption to the movement of men and materiél was the way to success received the solid support of Arthur Tedder with whom Zuckerman had worked closely in the Mediterranean and who was by then Deputy Commander of the Allied Expeditionary Force. Tedder, in turn, convinced Eisenhower, the supremo of the Expeditionary Force.

Emmens was then involved in the analysis of bombing in support of the breakout from Normandy and the advance through France into Germany. One job, assigned to him by Zuckerman, was to assess the destruction of the bridges over the River Seine in impeding the escape of German forces from the Falaise Pocket. ‘Bridge interdiction’ was in favour, particularly by the U.S. Army Air Force, arguing that it would reduce troop and supply movements drastically. Zuckerman and his team were not convinced. With USAAF and RAF Bomber Command represented in Emmens’s small team, they found, after considerable work, that 90% of vehicles, 70% of tanks and at least 95% of the men who reached the Seine succeeded in crossing the river, despite the blown bridges.

Emmens was in charge of the post-war survey of town bombing—as a member of the newly named British Bombing Survey Unit. By then it was possible to compare the various estimates of the effects of the bombing on German cities, estimates including those made by Bomber Command, the scientists acting on the results of the surveys, as well as the real information from German sources. As his biography reports:

According to Emmens, the scientists came out of it very well and were nearer to the truth than any others, whose estimates were in general excessive. He was in charge of the survey of town bombing, which made it clear that until the chaos in Germany right at the end of the war, the Allied offensive had had little effect on either morale or production. Concentration on communications or fuel at an earlier stage would have been much more useful. At the start of the war, towns were about all that could be hit but, according to Emmens, rigorous training for greater accuracy and a switch to other targets should have followed.

Emmens (front row left). From Zuckerman 1978
Although civilians, members of the survey were given honorary commissions in the Royal Air Force

From the Natural History of Bombing and the heart of the scientific analysis of military operations, Emmens returned to the National Institute of Medical Research. His statistical nous was such that he became involved in a number of activities that used those talents in addition to working on deep-freezing spermatozoa with Alan (later Sir Alan) Parkes. Emmens had first got a job in Parkes’s laboratory in 1937. He had graduated in Zoology with Physiology as a subsidiary subject (having swapped Agriculture at Wye College for Zoology at University College London. He had then worked as a research student with J.B.S. Haldane on biometry but gave up that studentship when he was offered a permanent job with Parkes. His job was to establish biological assays for human sex steroids and gonadotrophins, biological assays because no other methods were available for these substances, often of unknown chemical composition, at the very low concentrations present in blood and urine. Defining the dose or concentration of a hormone by its biological activity was essential and required considerable statistical input. Emmens, in the then burgeoning field of endocrinology, also began work on the biological effects of oestrogens.

In 1947, Emmens was invited to join the new department of veterinary physiology in the University of Sydney. He accepted and sailed for Australia in March 1948 with his wife and family.

From Centaur (Journal of the Sydney University Veterinary Society) 1948

In Sydney, he had a hard time from some members of the veterinary profession in the vet school: ‘Emmens was not a vet, was not a blood and guts physiologist, was not even a physiologist’. So entrenched in view were these vets—echoing it has to be said their counterparts in the U.K.—that I have been told stories of their anti-Emmens antics by former members of staff and by former veterinary students. Many of the latter, I became aware, thought Emmens and his departmental staff from several science disciplines, a breath of fresh air. The research output of his very small department exceeded that of all the rest of the veterinary school.

Emmens was highly active in Australian and international science, continuing for some time his own interests in bioassays and biological standards and in the actions of oestrogens and anti-oestrogenic compounds. He is remembered as always in a hurry, not to suffer fools gladly, and of ‘incandescent temper’. Present-day university ‘managements’, spouting HR platitudes from every orifice, would be horrified—and wrong.

Although his biographers report that he first became interested in pond life at the age of 10. He then started to keep freshwater species while at school and tried to keep marine species collected during family holidays to the coast. It was on his move to Sydney that he began fishkeeping in earnest. He bought a large house by the shore of Sydney Harbour. The basement he filled with over 70 tanks ranging from 20 to 450 litres. As he became successful in keeping and breeding fish* he began writing about them in magazines for aquarists. His first book, published in 1953, was entitled Keeping and Breeding Aquarium Fishes. It was published by Academic Press in New York (not as stated in his biographical memoir). Thereafter his books were published by TFH Publications, owned by the later disgraced and infamous Herbert Axelrod who was sometimes Emmens’s co-author, with an increased number appearing after his retirement from the university. These book covered freshwater and marine aquaria. Axelrod is described as Emmens’s friend by the latter’s biographers. If that was so, then perhaps stories of Axelrod’s dubious business methods and nomenclatural shenanigans over the naming of the Cardinal Tetra, Paracheirodon axelrodi, had not spread from the U.S.A. to Australia.

As far as I can ascertain it was Emmens who suggested in 1958 that ‘lactation’ in Discus fish, where the young feed on a skin secretion produced by the adults, was likely to be controlled by the hormone, prolactin, like milk secretion in mammals and crop ‘milk’ in pigeons. That suggestion was borne out by subsequent experimental work in Japan and Germany.

Clifford Emmens died in Sydney on 18 June 1999. An obituary in Tropical Fish Hobbyist, the magazine then owned by Herbert Axelrod, described Emmens as “scientist, teacher, author, aquarist, judo black belt, ballroom dancer” His biographers considered that ‘an apt summary of this complex and remarkable man. What could have been added is that he was a much respected and admired colleague’.

*For a long time I thought Emmens had been solely concerned with keeping and breeding fishes. However, I found an article he had written for the old Water Life magazine in the UK in 1955. It was on keeping the small Australian frogs (or ‘toadlets’) of the genus Pseudophryne. Some of these species are now classed as ‘critically endangered’ or ‘endangered’. Emmens photographed P. corroboree (the Southern Corroboree Frog) for his article. It is ‘Critically Endangered’ with only tens of adults being recorded now being recorded in the wild.

Stone GM, Wales RG. 2004. Clifford Walter Emmens, 1913-1999. Historical Records of Australian Science, vol.15, no.1, 2004 (see here for the version as a biographical memoir).

Zuckerman S. 1978. From Apes to Warlords. London: Hamish Hamilton.