Friday 25 September 2015

How do hummingbirds drink nectar? And what about sunbirds?

The recent paper Hummingbird tongues are elastic micropumps published in Proceedings of the Royal Society has attracted attention in news media throughout the world.

The long-held notion that nectar flows by capillarity into grooves in the tongue that effectively form cylinders along part of its length seemed, first of all, to be supported by photographic studies and theoretical calculations. That paper was published, also in Proceedings of the Royal Society, in 2012 and entitled, The hummingbird’s tongue: a self-assembling capillary syphon.

Results in the most recent paper by Alejandro Rico-Guevara, Tai-Hsi Fan and Margaret Rubega were obtained by using high-speed cameras in eighteen species. It appears that the grooves, empty by compression inside the bill during protrusion and remain compressed until the tips of the tongue contact the nectar. The grooves then expand and fill completely with nectar. The tongue is withdrawn into the bill and the process is repeated. In other words, the observations are compatible with the mechanism being an elastic pump. With capillarity, these authors argued, the grooves should open to form cylinders before the tip of the tongue touches the nectar and a fluid meniscus should be apparent in the grooves. Those properties were not seen.

A video from the University of Connecticut (where two of the authors of the 2015 paper are based) can be seen here:

By contrast, the authors of the 2012 paper did report a meniscus in one species of hummingbird feeding from an artificial feeder, and the question is whether some difference in methodology or condition of the birds was responsible for the variation seen in the high-speed videos taken by the two groups. Two videos from that paper are shown here and here.

I suspect we have not heard the last of this story. It may not be one of those cases of either/or but of both, depending on circumstances as yet unknown. I can only add the observation that leaving things to capillarity does seem somewhat passive. In birds with such a high metabolic rate would it not be expected that an energy efficient pumping mechanism, faster than capillarity, would offer a selective advantage?

Finally, of course, the question must be asked: what is the mechanism in sunbirds, those unrelated, non-hovering nectarivores, of the Old World? Similar rates of nectar removal from flowers and artificial feeders to those recorded in hummingbirds have been reported*.

A female White-breasted Sunbird (Nectarinia talatala) that lived
in my office and at home at weekendsfor several years before
it went to join a male. It was fed exclusively on an artificial
nectar I designed specially for sunbirds

As a postscript it is worth noting that the titles of scientific papers are phrased very differently indeed. This is Gadow’s title for a paper on the subject that appeared in Proceedings of the Zoological Society of London in 1883 (pp 62-69): On the suctorial apparatus of the Tenuirostres.

It must be time to apply my suctorial apparatus to my dinner.


†Kim W, Peaudecerf F, Baldwin MW, Bush JWM. 2012. The hummingbird’s tongue: a self-assembling capillary syphon. Proceedings of the Royal Society B 279 4990-4996.
‡Rico-Guevara A, Fan T-H, Rubega MA. 2015. Hummingbird tongues are elastic micropumps. Proceedings of the Royal Society B 282 20151014.
*Paton DC, Collins BG. 2006. Bills and tongues of nectar-feeding birds: A review of morphology, function and performance, with intercontinental comparisons. Australian Journal of Ecology 14 473-506.

Tuesday 22 September 2015

Found on a Hong Kong beach: What lifeforms are these?

AJP reports finding lots of these on the beach on the island of Po Toi last Sunday (a favourite place for birdwatchers since it is a major place for migrants to drop in) south east of Hong Kong island.

The discs are 3-4 cm in diameter.

After some searching he identified them as the remains of Porpita porpita, the Blue Button, superficially a jellyfish, but actually a colony of hydrozoan polyps, which is found in tropical and sub-tropical seas.

Now included in the Phylum Cnidaria, in our day they were in the Coelenterata along with the ctenophores.

Monday 21 September 2015

Hong Kong 70 Years Ago: Herklots the biologist; North the civil servant

The website Gwulo: Old Hong Kong is superb. Those who have followed the daily updates that show entries from the diaries written by internees in Hong Kong before, during and after the Japanese surrender, 70 years ago, will have noticed the name of Dr Geoffrey Alton Craig Herklots (1902-1986).

I hope to write more about Herklots later but at the time of the Japanese invasion in December 1941 he was Reader in Biology at the University of Hong Kong; he had joined the university in 1928 to start the teaching of biology. He later wrote the books, Hong Kong Birds and The Hong Kong Countryside. In addition to his job in the University, Herklots also became involved in Government work. In 1937, for example, he was appointed Superintendent of the Botanical and Forestry Department. He set up a Fisheries Research Station in the University and he founded, edited and contributed to The Hong Kong Naturalist.

Herklots was part of the group of underfed, ill and exhausted internees led by Franklin Gimson (who had himself sworn in as Acting Governor) out of Stanley to re-establish British rule immediately after the Japanese capitulation. The intense activity of those few days, before the arrival of the Royal Navy taskforce, is described in Philip Snow’s The Fall of Hong Kong (Yale University Press, 2003). Against a background in which U.S. army generals and Chiang Kai Shek’s Nationalists were trying to ensure that the latter took over Hong Kong, there were local deals to be done with the Japanese and with a local triad gang in order to maintain law and order as armed, looting gangs ran riot.

Camellia hongkongensis
from The Hong Kong Countryside
In the newly restored Government Herklots became Secretary for Development and had a particular responsibility for fisheries and agriculture. He became greatly involved in the business of survival both before and after the surrender to the Japanese in December 1941. Before the Japanese crossed the border, the Director of Medical Services, Selwyn Selwyn-Clarke, asked Herklots to devise a ‘siege biscuit’ that would provide the population with basic nutrition. With Thomas Edgar, a master baker, and after numerous trials, a successful product was launched. On the day before the Japanese attacked, a successful biscuit was produced that also contained calcium carbonate and shark liver oil.

In the Stanley internment camp, Herklots played closely involved with the welfare and education of its inhabitants who were malnourished, in terms both of quantity and quality, terrorised and short of medical supplies (even Red Cross parcels were held and not distributed by the Japanese). Herklots was a member of the organising Camp Temporary Committee, continued with running the University as far as was possible, gave general lectures ('Tropical Seas', for example) and continued work on trying to counter nutritional problems in the internees. This extract from Gwulo shows what he was involved in:

Thursday 1 July 1943
More than 18 months of poor nutrition are taking their toll. One of the most alarming developments is the occurrence of eye problems due to B vitamin deficiency. The camp's doctors are trying to tackle the problem, and today Dr Kenneth Uttley writes in his diary:
     Now that Lane Crawford’s baker Mr Edgar has been interned here, I have set Herklots and him on to the problem along with myself; we have cut down the amount of sugar required and are making more efficient use of the soya bean residue left after making the soya bean milk for the children and invalids. We have at last what appears to be a fairly active yeast and Geoffrey and I dispense it daily at 2pm to the eye cases and certain other B2 deficient cases.  Geoffrey and Edgar are busy most of each morning working on the yeast and are thoroughly enjoying themselves. We even entertain the idea of making yeast for the whole camp, but that will have to wait.
     Former Secretary to the Health Department J. I. Barnes reports that he was almost blind from vitamin deficiency but 'fully recovered' his sight after two doses of yeast - he got the second because he was a 'special worker' and most cases only got one dose. His job was looking after the camp stores - he slept there at night to prevent theft.

The internees in Stanley had also done a lot of thinking and planning. Before the arrival from London of a new civil administration to work under the temporary military administration, the ex-internees worked hard. At the speed that characterises the way things were done in Hong Kong, Herklots launched his new scheme for fish marketing on 12 September, less than a month after the Japanese capitulation, a week before the formal Japanese surrender and only 13 days after Harcourt’s ships and troops arrived in the harbour.

Herklots sketched his encounter with a large jellyfish
(The Hong Kong Countryside)
The other internee re-establishing British rule of interest here is Roland Arthur Charles North (1889-1961), Secretary for Chinese Affairs in the pre-war government and acting Colonial Secretary. I have written about him here*, since I have his complete run of The Hong Kong Naturalist on my bookshelves.

Herklots and North (a member of the old guard in the Colonial Service with whom Gimson disagreed on the way in which Hong Kong should be governed in the future) were members of the Hong Kong Government that seized the day and which issued its famous first communique since Christmas Day 1941 at 11.00 on 30 September 1945 The communique signalled loud and clear in thirteen words both immense relief and the carrying of a very big stick. Was it, I wonder, drafted by Duncan Sloss (1881-1964), temporary Director of Information and Vice-Chancellor of the University from 1937 until 1948?

Rear-Admiral Harcourt is lying outside Hong Kong with a very strong fleet…

The University of Hong Kong's building for biology in the 1930s
In the 1960s it housed the University Press. Before its conversion for biology  in 1928
it had been used for staff housing. After biology moved to the Northcote Building
it was briefly used as a women's hostel; Han Su-yin, under her university name of
Dr Elizabeth Tang was its sub-warden.
(from Bernard Mellor's The University of Hong Kong. An Informal History)

*I have made some recent additions to this post of 20 October 2013.

Wednesday 16 September 2015

Roger Akester (1922-2015) Avian Functional Anatomist

I was sad to see the death announced today in The Times of Roger Akester (Arthur Roger Akester), aged 92, on 29 August in Cambridge.

Roger Akester, veterinary anatomist at Cambridge from 1959 until 1991, will be remembered by all those with an interest in how birds work for his seminal contributions, made during the 1960s and obtained by x-ray and radio-opaque tracers, on the control of blood flow through the renal portal blood vessels and the passage of urine from the cloaca into the rectum and caeca by reverse peristalsis. The latter finding, which at the time was unexpected and contrary to the accepted view, provides the opportunity for modificaton of the salt and water content of the urine and for the uric acid to be metabolised by gut bacteria into useful products like volatile fatty acids; in other words, the recycling of waste products to get a second bite of the cherry.

The result of the mixing of urine, with its white uric acid, and faeces in the hind gut of birds is that both are voided together, as those who have been the target of a passing bird will testify. When I have to clean my car after an aerial assault by gulls that abound here, I cannot help thinking of both Erik Skadhauge, who went on the work on the salt and water aspects of modifying urine in the hind gut, and Roger Akester who discovered what was happening.

In the few hours since seeing the announcement in The Times, I have been able to find this radiograph (reproduced by W.J. Cliff in his book, Blood Vessels, Cambridge University Press, 1976), originally from Roger Akester's paper, on blood flow in the renal portal vessels and its control by the renal portal valves:

Tuesday 15 September 2015

Gustav Tornier and his tortoise, the Pancake Tortoise

Gustav Tornier
Mentioning what would now be regarded as completely crazy ideas of how a dirty environment induced the appearance of fancy goldfish in China and his hypothesis of 'plasma weakness' in my post on Dorothy Sladden and Ernest MacBride, I should note that Gustav Tornier (1859-1938) is best remembered for two things. The first was his incorrect representation of Diplodocus, a sauropod dinosaur, as a crawling, sprawled-leg reptile. The second is Tornier's Tortoise, now usually called the Pancake Tortoise, from rocky areas of East Africa, named after him by Siebenrock in 1903.

Siebenrock named the species Testudo tornieri; it is now Malacochersus tornieri. It was once commonly imported for the specialist reptile collector. Largely now protected, it is now commonly bred in captivity. It lays a single egg at a time—there isn't room for a clutch inside the flattened body.

This is the title page of Siebenrock's paper:

The start of the description of the new species:

The dedication to Tornier:

And the drawing:

And here is the nice short title of the Journal:

It was published in volume 112, pages 439-445.

We wrote about a then new finding in 1973 in an article in the Aquarist and Pondkeeper (38, 237-238):

The Pancake or Soft-shelled Tortoise...must be the oddest of all the land tortoises. The shell, which has the consistency of thick parchment, is thin and flat and entirely lacks a domed carapace. The bony plates which underlie the shell have large apertures so that the whole arrangement gives virtually no protection against predators. Early collectors found that these tortoises are extremely difficult to extricate from the crevices into which they run when disturbed, and suggested that not only do they wedge themselves in but actually inflate the body in order to press the shell against the walls of the crevice.
     In fact the ability to inflate was never checked although the story has been repeated from book to book since the 1920s with greater emphasis on the inflation than on the wedging action of the legs, even though Dr Robert Mertens had failed to find any evidence for inflation during the early 1940s. Drs L.C. Ireland and C. Gans of the State University of New York realised that the respiratory mechanism of tortoises probably would not allow the lungs to be inflated in order to distend the soft shell. Therefore they tested the response of Pancake Tortoises to being forcibly pulled from an artificial crevice they had been allowed to enter. Direct measurements of pressure in the lungs (reported in Animal Behaviour volume 20, pages 778-781, 1972) during this procedure clearly showed that there is no sustained inflation and that the tortoises depend on the wedging action of the fore- and hind-limbs to hold tightly in the crevice...

Later studies have suggested another mechanism. Richard Moll and Michael Klemens (Chelonian Conservation and Biology 1996 2, 26-35) looked at tortoises in the wild and reported that they could expand their bodies. They showed the presence of an extremely flexible diamond-shaped region on the plastron that protrudes when the legs are drawn in. This finding suggests that the lowered plastron region constitutes an important second type of wedge, and one that could easily have been interpreted as inflation of the body with air.

This is a photograph of captive Pancake Tortoises from Wikipedia. I have not been able to find one taken in the wild.

By Dave Pape (Own work) [Public domain], via Wikimedia Commons

That's him! Harold Munro Fox. A personal mystery solved fifty years later

Sometime early in 1965 I went for an interview for an overseas scholarship (overseas ones were funded by NATO) to work as a postgraduate student at the University of Hong Kong. The newly constituted Science Research Council was taking over from the Department of Scientific and Industrial Research as the British government's key funder of postgraduates. I remember very little about the interview, which was held at State House (demolished in the 1990s and after all but one Research Council were exiled to the outer darkness of Swindon) a then modern block in High Holborn in London, except for some very easy questions from an elderly man on the left. I also remember that I was not told who the three members of the panel were.

While looking up material for my jotting on Dorthy Sladden and Ernest W MacBride, I found myself looking at the photograph of the man on the left who dollied up the easy questions. It was Harold Munro Fox, FRS (1889-1967) best known for his work on animal pigments but also for his experiments which failed to replicate Kammerer's claims on regeneration in the sea squirt, Ciona.

Harold Munro Fox - from his Biographical Memoir
of the Royal Society

Saturday 12 September 2015

George Boyce (1920-95) of South Western Aquarists. Herpetologist

Some people have an influence far wider than their formal qualifications or occupation would suggest. In the world of herpetology in Britain of the 1950s and 60s, George Boyce, a pet-shop owner had a great influence on young people with an interest in reptiles and amphibians. Yes, he would sell you the animals but he was also a great enthusiast and advocate not only for reptiles but also for instilling a life’s interest in something worthwhile. This is a slightly modified version of this post on my other blog that deals with the history of the advances in keeping reptiles and amphibians.

In mid-1950s Britain dealers in reptiles and amphibians were rare for the simple reason that the market was small. Some larger dealers had gone out of business. Palmers of Camden Town was the really big one but did not specialise in reptiles. There were wholesale dealers selling to small pet shops but the main ones catering for enthusiasts and zoos were Robert Jackson in Cheshire and George Boyce in London. For a few years they were the only regular source.

George Boyce owned South Western Aquarists, a tiny shop at 2 Glenburnie Road, Tooting. It was a place where people, amateurs and professionals went to talk about and occasionally buy reptiles and amphibians. It was somewhat unusual because the reptiles and amphibians were not usually kept on the premises. From his lists which could be had by post, you could either get them delivered by rail to all parts of the country or you could write or phone to ask to look at something on the list; he would then bring the animals with him from home on the appointed day. Impulse buying was impossible. In the times I visited the shop over the years (1959 until 1982) I only ever saw a few lizards in one tank once. There were a few tanks of tropical fish and the then usual supplies of pet food. Conversations were frequently interrupted by the arrival of a little old lady to buy a pound of budgerigar seed or some dog or cat food. This local trade received the benefit of a level of attentive service verging on the obsequious before the owner returned to the subject of the conversation.

There is virtually no information on George Boyce or South Western Aquarists on the internet. However, I was delighted that he does make an appearance in the autobiography of Ken Livingstone, You Can’t Say That published in 2011 (London: Faber and Faber). For those readers not in UK I should explain that Ken Livingstone is a politician of the left and was Mayor of London from 2000 until 2008. He was a Member of Parliament from 1987 until 2001. He is also well-known as a keeper of reptiles and amphibians with the press usually referring disparagingly to ‘his newts’.

In describing his early life, he wrote:

Saturday afternoons were often spent at a pet shop on Tooting, chatting to the owner George Boyce about his imported reptiles, his Rotary Club activities and his Tory beliefs…

He goes on:

…Sadly, any chance of romance was dramatically reduced by my herpetological hobby. In all the Saturday afternoons I spent chatting to other reptile enthusiasts in George Boyce’s pet shop, only one young woman ever came in and she was dating another collector.

Ken Livingstone also reproduced a letter he had from George Boyce while backpacking to and from West Africa in 1966 which ends:

All the ‘lads’ and ‘lasses’ at the shop have asked me to convey to you their best wishes for your continued success in the termination of your journey. To these felicitations, Ken, I would add those of my own and of course Doris. Yours as ever, George.

I never went to Tooting on a Saturday on my rare visits to London. There was only ever George, me and his local customers. I remember him describing: visiting Jack Lester, Curator of Reptiles at London Zoo until he died in 1956, and Margaret Southwick, his assistant, on evenings when consignments of reptiles had arrived at the Zoo and were being unpacked; fishing at Frensham Ponds after the Second World War and catching large European Terrapins that had obviously been released there; the difficulties of dealing with exporters who would send what they had rather what was ordered; exporting imported animals to zoos in the U.S.A.

A frequent visitor to the shop and one who had just left when I got there was Dr Ian Wesley Whimster (1924-1979), Reader in Pathology at St Thomas’s Hospital Medical School. Part of his research was on the pigment cells in the skin of lizards; to that end he established a captive colony of Leopard Geckos.

He was a regular at meetings of the British Herpetological Society and wrote an article for the Journal on keeping crocodilians. He was there at the first meeting I attended (Summer 1961, I think) in the rooms of the Linnean Society in Burlington House. At that meeting everybody sat around a large mahogany table as live reptiles were passed around. I remember an impressive Leopard Tortoise and some superb Australian skinks owned by a woman sitting next to me. I asked how she had got so many and in such good condition. She explained that her husband was a pilot with B.O.A.C., the long-haul British airline that was merged with B.E.A. into British Airways, and he simply picked them off the taxiways and surrounding scrub at Sydney airport as he walked to his plane.

We also know from an article in Fishkeeping & Water Life that in 1958 he appeared on BBC Children’s Television describing Fish and How to Keep Them. In the BBC Genome project documenting BBC programmes the programme is there (20 January 1958) but he does not get a credit.

I have had some difficulty in finding more about George Boyce. However, thanks to his being in 1966 the executor of his father’s will (where he was described as aquarist and herpetologist) which was traced through a family history search website, I now have more information. George Frederick Boyce was born on 7 October 1920 in the Dorking Registration District of Surrey; in 1947 he married Doris L. Harrison in Croydon, Surrey. He died in 1995 in the Wandsworth Registration District of London.

I do not know when his shop closed; my guess is the mid- to late-1980s (my last visit to the shop was in November 1982). From advertisements in Water Life, it is clear that South Western Aquarists was operating in the late 1940s. Advertisements from 1950 mention a D.C. Crisp who must have been a partner, and Water Life (July-August 1950) in describing an aquarium show in London notes, D.C. Crisp of South London [sic] Aquarists made an intriguing picture, entering the hall with an alligator on a lead. Later in the 1950s, only the name of G.F. Boyce appeared on price-lists etc. and I have found no further clues on the role or identity of D.C. Crisp.

Here is an advertisement that appeared in Fishkeeping & Water Life in 1958:

Finally, a photograph of my Mississippi Alligator, photographed on the lawn of my grandmother’s second cousin’s house in Hendon, the afternoon I collected him from Tooting and eventually the subject of a note in British Journal of Herpetology*.

As always, any further information on George Boyce is welcome. Please contact me if you have any.

*Peaker, M (1969) Active acquisition of stomach stones in a specimen of Alligator mississippiensis Daudin. British Journal of Herpetology 4, 103‑104

Tuesday 1 September 2015

A Giant Giant Salamander in Today's South China Morning Post

My Hong Kong correspondent sent me a snippet (as a follow up to my post of 17 December 2014from today's South China Morning Post (70 years and two days since the first issue was printed after the Japanese capitulation and as the interned British officials took control and issued a first communique at 11 am: Rear-Admiral Harcourt is lying outside Hong Kong with a very strong fleet...) 

Meet Han Han, the 40 kg giant salamander

SICHUAN — Photos have surfaced of a Chinese giant salamander weighing up to 40kg and measuring about 1.5 metres in length in Yibin, local media report.
     The salamander, named Han Han, is 23 and belongs to a man, surnamed Feng, who owns a salamander breeding farm, the West China City Daily, reports.
     According to Feng, Han Han has been given the all-round VIP treatment so it can continue to grow, including giving it wild fish to eat and housing it in a pool built into a natural cave.