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Science News

156 Posts authored by: John Jackson

The great majority of the more than 400 families of snails are found only in the sea, while about 5% of them are exclusively freshwater. Very few snail groups are common in both environments and just three marine families have rare freshwater members.


One of these is the Littorinidae (periwinkles), familiar from rocky shores. In the nineteenth century three freshwater periwinkle species (genus Cremnoconchus) were discovered in the mountainous Western Ghats of India, living in fast-flowing streams at altitudes between 300 and 1400 m. These have not been studied for over 100 years.


Cremnoconchus.JPGFigure from the original description of Cremnoconchus (images 1-7) Image courtesy of Biodiversity Heritage Library.


In a collaboration with scientists from the NHM's partner organisation the Ashoka Trust for Research in Ecology and the Environment (ATREE), Bangalore, David Reid revisited the type localities of the three known species to collect new specimens. (The type locality is the place in which the reference specimen was found that was originally used to describe and name the species.) These were studied to find out more about the snails and allowed the relationships between the species to be investigagted in more detail and revised.  There are distinctive differences between the species particularly in terms of their radula (the rasping tongue of snails), their reproductive systems and the calcified operculum (the disc that fits into the shell opening when the snail retreats into the shell, providing additional protection from predators and desiccation).


In addition, an unknown radiation of six new Cremnoconchus species was discovered in the central Western Ghats, 500 km south of the previously known range where David and his collaborators looked at the known species.


Cremnoconchus is interesting in evolutionary terms: the current evidence suggests that its closest living relatives are marine snails found only in New Zealand and Australia, suggesting that the ancestral population was split by the breakup of the ancient continent Gondwana during the Cretaceous, between 145 and 65 million years ago.  However, more evidence and DNA studies would be needed to confirm this hypothesis.

Each of the six new species was restricted to a single stream system on the steep western escarpment of the Deccan Plateau, with limited overlap in distribution in two places.  This suggests that populations of ancestral species were isolated by waterfalls or other features allowing evolutionary divergence over time The habitat of these snails is fragile, being very limited in scale and threatened by tourism, road construction and domestic pollution: all the species are judged to be endangered.


Reid, D.G., Aravind, N.A. & Madhyastha, N.A. (2013) A unique radiation of marine littorinid snails in the freshwater streams of the Western Ghats of India: the genus Cremnoconchus W.T. Blanford, 1869 (Gastropoda: Littorinidae). Zoological  Journal of the Linnean Society. 167: 93-135.
DOI: 10.1111/j.1096-3642.2012.00875.x


Michael Kuhlmann and colleagues have put the beta version of the “Checklist of Western Palaearctic Bees” online ( using the NHM-developed Scratchpads as a platform.


Bees are the most important pollinators worldwide and the checklist provides access to taxonomic information and distribution data on country level to about 3350 bee species in 102 genera in the western Palaearctic region, with almost 2000 species recorded for Europe alone. The site contains regularly updated information from both published and unpublished sources including data from a whole range of private and public collections that are provided by European wild bee experts. The checklist reflects the current state of knowledge on the taxonomy and distribution of western Palaearctic bees, making it a prime source of information not only for taxonomists but also ecologists and agricultural scientists.


The checklist project started in 2008 and it quickly became clear that taxonomic expertise is globally lacking for several genera and that this gap is likely to grow quickly due to the progressive ageing of the community of bee taxonomists . The places most heavily affected by the loss of taxonomic knowledge are the “hotspots” of species diversity and endemism around the Mediterranean, in Turkey and the Middle East. Unfortunately, these are the areas that are most likely to be heavily affected by climate and landscape change. For this reason it seems possible that most of the predicted changes and losses of unique fauna will go unnoticed.


IMG_0579.jpgBombus (Pyrobombus) pratorum, the early bumblebee on Pentaglottis sempervirens


The Parasites and Vectors division in Life Sciences  has been re-designated as the World Health Organisation Collaborating Centre for Identification & Characterization of Schistosome Strains & their Snail Intermediate Hosts until December 2016.  This is in recognition of the importance of their work and expertise on Schistosoma species, the parasitic blood flukes that cause  the debilitating disease schistosomiasis, and is a good example of how the NHM contributes to the solution of global problems of health and wellbeing.


The group has had a  long-standing research focus on Schistosoma parasites, initially born from research on the molluscan (snail) intermediate  hosts and host-parasite interactions. Schistosomes have a two-host life cycle  involving an intermediate snail host and a definitive vertebrate host. The  relationship between the schistosomes and the snail is such that precise  identifications of both are required in order to understand the transmission  and the epidemiology of the disease. By researching the factors involved in Schistosoma parasite - snail host infection dynamics, the  team can provide expert advice to countries affected by schistosomiasis.


What is schistosomiasis?  A staggering number of people are infected by  schistosomes, over 200 million people worldwide with over 700 million people at  risk of infection. It is a disease of low socio-economic status, affecting the  poorest communities and most neglected, vulnerable people; it is therefore  classified as a neglected tropical disease (NTD). Infants and children are  especially prone to infection and the damage caused by schistosomes can lead to  blood in urine, painful urination, diarrhoea, bloody stool, anaemia, stunted  growth, enlarged liver and spleen, bladder and liver damage. In certain cases  early childhood infections can lead to bladder cancer and liver fibrosis in  adulthood. Over 90% of infected  people live in sub-Saharan Africa, and the NHM team concentrates its research  efforts in areas such as Tanzania, Niger and Senegal, working with teams in  country to help find better solutions to reduce the impact of this debilitating  disease.


Research at the NHM - The group at the Museum  is involved in a number of collaborations with research organisations here and  overseas:


  • SCORE -  The Schistosomiasis  Consortium for Operational Research and Evaluation (SCORE), funded by the Bill and Melinda Gates  Foundation aims to aid national control programs by defining the best intervention  methods and cost effective strategies for schistosomiasis control in  sub-Saharan Africa. Part of the research undertaken at the NHM monitors the  impact of Praziquantel (the only oral drug effective in treating all forms of schistosomiasis  in sub-Saharan Africa), on parasite populations, in order to monitor for the  potential development of drug resistance.
  • SCAN -  The Museum, with funding from the Wellcome Trust, has set up a rapidly  expanding schistosome repository called SCAN (Schistosomiasis Collection at the  NHM) which preserves and documents schistosome samples collected from Africa in  order to provide material for researchers both within and outside the Museum.  
  • ZEST -  ZEST (Zanzibar  Elimination of Schistosomiasis Transmission) is being led collaboratively by  the Zanzibar Ministry of Health and the Museum’s David Rollinson (funded by  SCORE), director of the NHM -WHO collaborating Centre. This ambitious programme  is attempting to eliminate schistosomiasis – the first time in a sub-Saharan  African country.


London Centre for  Neglected Tropical Disease Research - The Museum is also a  founding member of the new London Centre for Neglected Tropical Disease  Research, launched on the 30 January 2013 in collaboration with the London School  of Hygiene and Tropical Medicine and Imperial College. This important new  initiative is a valuable step forward as it brings together world-class skills  and expertise to answer important research questions concerning the biology and  control of neglected tropical diseases in partnership with governments, the  private sector, academic institutions and other key NTD centres.



Ian Owens
Director of Science


Lorna Steel and collaborators have produced a paper that shows that modern-day killer whales are adapted to use the same hunting and feeding mechanisms as ancient crocodiles from more than a hundred million years ago.


They discovered that two crocodylians that grew to over 4m long and swam in Britain's shallow seas around 150 million years ago, were adapted to eat  prey similar to that of modern-day killer whales. Dakosaurus and Plesiosuchus both had robustly-built skulls and their anatomy indicates the capability to deliver great biting force.



Reconstructions showing the maximum body lengths for the Geosaurini genera present in the late Kimmeridgian-early Tithonian of Western Europe. 

The species from top to bottom are: Geosaurus giganteus, Dakosaurus maximus, Torvoneustes carpenteri and Plesiosuchus manselii. The maximum known body lengths of Torvoneustes and Geosaurus are from Young et al. [14], while those of Dakosaurus and Plesiosuchus are from this paper. The human diver is 1.8 m in height. All metriorhynchid life reconstructions are by Dmitry Bogdanov.  From Young et al. (2012) Creative Commons Attribution License for image and caption.


What is of particular interest is the parallel with the two types of North Atlantic killer whale: one smaller type which eats mainly fish prey, often by suction, and which has extensive wear and breakage on the teeth. The second larger type has little tooth breakage and eats other cetaceans. 


In the ancient crocodylians, there is extensive evidence for a similar dichotomy - in short Plesiosuchus is larger and shows little dental wear, with a wide effective gape that allowed many teeth to come into contact with the prey, so likely to be a specialist feeding on other marine reptiles. Dakosaurus was smaller, with considerable tooth wear and a shortened tooth row, suggesting a more general diet of smaller prey and suction feeding.  This difference in prey helps to explain how two large predators coexisted by avoiding competition.

Young, M.T., Brusatte, S.L., Brandalise de Andrade, M., Desojo, J.B., Beatty, B.L., STEEL, L., Fernandez, M.S., Sakamoto, M., Ruiz-Omenaca, J.I., & Schoch, R., 2012. The Cranial Osteology and Feeding Ecology of the Metriorhynchid Crocodylomorph Genera Dakosaurus and Plesiosuchus from the Late Jurassic of Europe. PLoS ONE 7(9): e44985. doi:10.1371/journal.pone.0044985


Helena Wiklund and Adrian Glover, together with collaborators from the USA and Sweden, have described six new species in the polychaete worm genus Ophryotrocha. The six new species were discovered on five whale-falls and two wood-falls in deep-sea water off the Californian coast.


Worms in the genus Ophryotrocha were until recently only known from shallow seas rich in nutrients, but as deep sea exploration has progressed, they have been found to be common in organically-enriched habitats such as hydrothermal vents,  cold seeps, whale-falls and in  areas impacted by human pollution (such as underneath fish farms), and  may well play an important ecosystem function role in the biodegradation  and decomposition of organic-rich materials. The new data also  highlight the poorly known biodiversity of the deep sea, and how  deep-sea species evolved.


The scientists have examined both the morphology and DNA of the worms.  Identification of one of the species is only possible by looking at differences in their DNA - its physical form is otherwise identical to another species found in the Atlantic. This is of additional interest because some marine species are found in all oceans but others will be found in only one.  The difference in DNA suggests the evolution of different species as a result of geographical separation.  It is suggested that there will be significantly more diversity in this and other groups in deep sea habitats with implications for understanding of these mysterious ecosystems.

Wiklund H, Altamira I, Glover AG, Smith CR, Baco A, Dahlgren TG. (2012) Systematics and biodiversity of Ophryotrocha (Annelida, Dorvilleidae) with descriptions of six new species from deep-sea whale-fall and wood-fall habitats in the north-east Pacific. Systematics and Biodiversity 10(2): 243-259.


Thomas Simonsen has published an invited peer-reviewed paper in Arthropod Structure and Development in collaboration with co-workers from the Finnish Museum of Natural History and Naturalis (Dutch Museum of Natural History) on the continuing importance of morphology in Lepidoptera systematics.


Taxonomy and systematics are areas of science that are focused on description, naming, classification and evolutionary relationships of living things.  Such science is the fundamental reason for the existence of large natural history collections, and traditionally the focus has been on morphology - the use of combinations of physical characters such as number of legs, wing patterns or body form.  The differences in these characters between species can be compared and allow identification - so a fly will have one pair of wings but a bee will have two pairs, for example. Over time, different species and groups have diverged as a result of evolution and in general become progressively more different in form.


However, while morphology is a key tool in understanding diversity, evolutionary difference can be seen also in molecules, particularly DNA.  DNA of different species can be compared and the degree of difference used to assess patterns of evolution and relationships.  The use of DNA in taxonomy and systematics is of increasing importance and museum collections are of great value in this new science - a purpose never suspected by those who started to assemble them in the 18th and 19th Centuries.


Wallace birdwing NaturalHistoryMuseum_PictureLibrary_056153_IA.jpgOrnithoptera croesus, Wallace's golden birdwing butterfly - a member of the Paplionidae family


Some scientists have argued that DNA alone will be used in future to assess diversity and to identify species: it is after all DNA differences that are the root cause of morphological difference - so why use both?  There are in fact a number of reasons why morphological techniques will be of continuing importance - Thomas and colleagues explore the relative value of morphology and molecular information for large groups of butterflies in this paper.


They reviewed the morphological characters that are important for understanding butterfly phylogeny and evolution in the context of large-scale molecular phylogenies (evolutionary classifications) of the group. In particular, they were interested in what the molecular evidence was able to tell them about the evolution of morphological features - so for example, were characters that are used to separate distantly related groups actually caused by large genetic differences?


They looked in particular at the families Papilionidae, Nymphalidae and Hesperiidae which have all been studied with a combination of morphological and molecular data in recent years. What they found was that a  scientifically more valuable classification emerged not from using either molecular or morphological techniques, but from using both in combination. They argue that morphology still has an immensely important role to play in butterfly (and insect) phylogenetics - including its value in understanding how the whole organism is important in evolutionary changes, natural selection and diversity.  


Simonsen, T. J., de Jong, R., Heikkilä, M. & Kaila, L. (2012). Butterfly morphology in a molecular age – does it still matter in butterfly systematics? Arthropod Structure and Development. 41: pp. 307-322.


Ralf Britz and his Smithsonian colleague David Johnson have published a paper in the Journal of Morphology on the development of the sucking disc of remoras. Remoras are a group of marine fish that usually attach themselves to sharks or other large fish such as manta rays with their sucking disc.  This lifestyle appears not to harm the shark, nor does it bring any benefit: depending on the species of remora, they eat fragments of the larger fish's food that fall from its mouth;  faeces; or the larger fish's parasites.


Echeneis NaturalHistoryMuseum_PictureLibrary_009079_Comp.jpgEcheneis naucrates - watercolour painting by Sydney Parkinson made during Captain Cook's first voyage 1768-1771


Ralf's work on the sucker involved examination and comparison of fins of different species of fish to identify the homology of its components - homology is the term used to describe organs in two species that have the same evolutionary origin, despite sometimes different appearance and function (so the human arm and a bat's wing are homologous).  The remora's sucker is not found in other fish - is it a totally new organ, or is it a highly modified version of an organ found in other fish?


By studying the development of larval remoras ranging from 9.3 to 26.7 mm in length, they demonstrated that the skeleton of the sucking disc forms by enormous expansion of the dorsal fin supports and the bases of the associated fin spines. The evolution of a sucking disc from a regular spinous dorsal fin seems like a major step in evolution but is actually a gradual process involving small incremental changes of structures during development.

Britz, R. & G. D. Johnson. 2012. Ontogeny and homology of the skeletal elements that form the sucking disc of remoras (Teleostei, Echeneoidei, Echeneidae). Journal of Morphology, 273 (12) 1353-1366 , DOI: 10.1002/jmor.20063

Ralf has also published a paper with a Brazilian colleague, Mônica Toledo-Piza, analysing the egg surface structure of the poorly known and highly venomous freshwater toadfish Thalassophryne amazonica with the NHM's scanning electron microscopes (SEM). Eggs of this fish show a highly unusual and complex system of ridges and intermittent grooves that originate at the equator of the egg and run toward the animal egg pole and end in a spiraling pattern at the micropyle (the only opening for sperm to enter). This striking modification may help to increase the chances of eggs being fertilized.

Britz, R. & M. Toledo-Piza. 2012. Egg surface structure of the freshwater toadfish Thalassophryne amazonica (Teleostei: Batrachoididae) with information on its distribution and natural habitat. Neotropical Ichthyology, 10: 593-599.


Ian Kitching, together with colleagues at the University of California, National University of Singapore and the University of Erlangen, Germany, has published a review paper charting the history of Charles Darwin’s prediction of coevolution between a long-spurred orchid, Angraecum sesquipedale, and a long-tongued hawkmoth, Xanthopan morganii praedicta, from Darwin’s first observations in 1862 to the final demonstration of successful pollination in the wild in 2004.


Angraecum NaturalHistoryMuseum_PictureLibrary_012880_IA.jpg

Angraecum Sesquipedale


Darwin wrote in his 1862 work On the various contrivances by which British and foreign orchids are fertilised by insects, and on the good effects of intercrossing:


I fear that the reader will be wearied, but I must say a few words on the Angræcum sesquipedale, of which the large six-rayed flowers, like stars formed of snow-white wax, have excited the admiration of travellers in Madagascar. A whip-like green nectary of astonishing length hangs down beneath the labellum. In several flowers sent me by Mr. Bateman I found the nectaries eleven and a half inches long, with only the lower inch and a half filled with very sweet nectar. What can be the use, it may be asked, of a nectary of such disproportional length? We shall, I think, see that the fertilisation of the plant depends on this length and on nectar being contained only within the lower and attenuated extremity. It is, however, surprising that any insect should be able to reach the nectar: our English sphinxes have probosces as long as their bodies: but in Madagascar there must be moths with probosces capable of extension to a length of between ten and eleven inches!


A moth with such a long proboscis, Xanthopan morganii praedicta, was not described until 41 years after the publication of this book, and it was not observed to visit Angraecum until 1992, with further work to prove pollination since then.  Ian and colleagues discuss issues of co-evolution and predation in this excellent paper.


Xanthopan morganii praedicta NaturalHistoryMuseum_PictureLibrary_037535_IA.jpg
Xanthopan morganii praedicta

Arditti, J., Elliott, J., Kitching, I.J. & Wasserthal, L.T. 2012. ‘Good Heavens what insect can suck it’ – Charles Darwin, Angraecum sesquipedale and Xanthopan morganii praedicta. Botanical Journal of the Linnean Society 169: 403-432.


Ralf Britz and collaborators from the Conservation Research Group from St Albert's College, Kochi, Kerala have published a series of papers describing three new fish species from South India.


Pristolepis rubripinnis, Dario urops and Pangio ammophila were discovered during the January 2012 NHM-funded visit of Dr Ralf Britz to Kochi, to work with Dr Rajeev Raghavan. Historical specimens of the fish collection in the Natural History Museum collected by Sir Francis Day in the 1860s and 70s played an important role in the resolution of taxonomic and nomenclatural issues before the species could be described.


This series of papers highlights our incomplete knowledge of one of the most important biodiversity hotspots in Asia, the Western Ghats, a mountain range along the west coast of Peninsular India. Both Pristolepis rubripinnis and Dario urops are of particular interest in that closely related species are found in north-eastern India - it is not clear how this distribution arose because there are no river connections between the two areas that would have allowed ancestral populations to separate, migrate and diverge into different species. 

Britz, R., Kumar, K. & Baby, F. (2012). Pristolepis rubripinnis, a new species of fish from southern India (Teleostei: Percomorpha: Pristolepididae). Zootaxa, 3345: 59-68.

Britz, R., Ali, A. & Philip, S. (2012). Dario urops, a new species of badid fish from the Western Ghats, southern India (Teleostei: Percomorpha: Badidae). Zootaxa, 3348: 63-68.

Britz, R., Ali, A. & R. Raghavan. (2012). Pangio ammophila, a new species of eel-loach from Karnataka, southern India (Teleostei: Cypriniformes: Cobitidae). Ichthyological Exploration of Freshwaters, 23: 45-50.


Some metals are an essential part of the metabolism of living organisms - Iron, Calcium, Sodium and Potassium, for example.  Others can be poisonous in the short term or over time - Lead and Mercury are both familiar examples. 


However, the impact of these toxic metals depends first on the way in which they behave in chemical terms in the environment - whether they are available to be absorbed by the organism (bioavailable).  Second, it depends on the way in which they are treated by the organism once absorbed.  Some toxic metals are easily excreted by organisms; others can gradually accumulate to the point of toxic effect over time; yet others may be bound up by proteins and rendered non-toxic to be stored in relatively inert form inside the organism (bioaccumulation) so organisms can be described as tolerant of the toxic metals and may survive in polluted environments.


It has been proposed that the bioaccumulated concentrations of toxic metals in tolerant biomonitor organisms can be used as indicators of metal bioavailability - where bioaccumulated concentrations are high, bioavailability is high.  This could be used to predict the ecological impact of those metals on groups of organisms that are more sensitive to metal pollution - direct measurement of low levels of metal pollution impact over time for sensitive organisms is both difficult and expensive.


Phil Rainbow, Sam Luoma, Brian Smith (Life Sciences) and colleagues addressed this proposal in the mining-affected streams of Cornwall. Mines operated over many years, now disused, have resulted in soil and stream pollution by metal-rich tailings and ore. 


Their hypothesis was that metal concentrations in the caddisfly larvae Hydropsyche siltalai and Plectrocnemia conspersa, as tolerant biomonitors, indicate metal bioavailability in contaminated streams, and can be calibrated against metal-specific ecological responses of more sensitive mayflies. Bioaccumulated concentrations of Copper, Arsenic, Zinc and Lead in H. siltalai from Cornish streams were measured and related to the mayfly assemblage.


Caddis NaturalHistoryMuseum_PictureLibrary_002034_Comp.jpg

Caddisfly larva - showing its protective case made of stones and vegetation


They found that Mayflies were always sparse where bioavailabilities (measured from caddis) were high.  However, mayflies were abundant and diverse where bioavailabilities of all metals were low.  This was particularly evident when the combined abundance of two particular groups of mayflies (heptageniid and ephemerellid) was measured.


The results offer promise that bioaccumulated concentrations of metals in tolerant biomonitors can be used to diagnose ecological impacts on stream benthos (organisms living on the stream bed) from metal stress.


P.S. Rainbow, A.G. Hildrew, B.D. Smith, T. Geatches and S.N. Luoma (2012). Caddisflies as biomonitors identifying thresholds of toxic metal bioavailability that affect the stream benthos. Environmental Pollution 166, 196-207.mayfly NaturalHistoryMuseum_PictureLibrary_002019_Comp-1.jpg

Ephemera danica - the larva of a mayfly


The Convention on Biological Diversity (CBD) is an international agreement under the UN umbrella that focuses on biodiversity information, conservation and sustainable use. Most of the World's countries have signed up to the CBD since it was initiated in 1992. It represents a common understanding of what biodiversity is; who owns and controls genetic resources; what information is needed to protect biodiversity and make decisions about its use; and how countries work together on all sorts of issues.


Dr Chris Lyal of the NHM has developed a lot of expertise on policy,  collaboration and capacity building under the CBD.  He is the focal  point for the UK for the Global Taxonomy Initative, a CBD programme that  aims to share taxonomic information and expertise. As a scientist, Chris is an expert on the taxonomy of weevils, a group of beetles that are significant crop pests - this involves deep knowledge of classification, naming and description of new species from around the world.


The Conference of the Parties to CBD (COP) is held every couple of years and COP 11 is currently being held in Hyderabad in central India.  Chris is there on behalf of the  NHM and has been in discussion with delegates from governments and other organisations on the science behind biodiversity and CBD initiatives.


One of the foci for CBD is invasive species.  There have always been natural patterns of change in the distribution of plants and animals. However, when humans cause species to be introduced - by accident or design - to new areas of the World they can cause major impacts.  They may become pests on crops or cause unexpected declines in natural biodiversity, for example, and can have huge economic costs. 


A new Global Invasive Alien Species Information Partnership has been formed to share and develop information on invasive species and to support development of expertise. Chris Lyal attended the inaugural signing of the partnership agreement and will be leading the NHM's contribution.


Chris at COP.jpg

Chris (standing) signing the GIASIP agreement on behalf of the NHM


One-day meeting sponsored by the QRA, QUAVER, NERC and the NHM

Wednesday 19 September 2012, 10 am – 6 pm

Flett Theatre, Natural History Museum. 


Confirmed speakers:


Tony Stuart (Durham) – Megafaunal extinction and survival, with special reference to northern Eurasia

Adrian Lister (NHM) – Mammoth extinction, refugia, and the synergy of climate and people

John Stewart (Bournemouth) & Chris Stringer (NHM) – Range shifts and extinction of Neanderthals and other human populations in the Late Quaternary

Ian Barnes (Royal Holloway) - Applying ancient DNA to Late Quaternary extinctions

Judy Allen, Yvonne Collingham & Brian Huntley (Durham) – Modelling vegetation change and  Late Quaternary extinctions

Martin Street (Neuwied) – Implications of the Western and Central European Late Upper Palaeolithic archaeological record for Late Quaternary Extinctions

Sam Turvey (ZSL) & Susanne Fritz (Frankfurt)  – The ghosts of mammals past: global patterns of mammalian extinction during the Holocene

Jennifer Crees (Imperial): Large mammal extinctions in Holocene Europe: case closed?

Kenneth Rijsdijk (Amsterdam) & the Dodo Research Programme team - Climate induced mass mortality vs. human induced extinction: an interdisciplinary analysis of a dodo mass grave on Mauritius

Ben Collen, Lucie Bland & Martina Di Fonzo (ZSL) – Wildlife in a changing world: predicting how populations decline to extinction

Kate Jones (UCL) - Current and future extinctions: windows into the past


For full programme details and registration (required), please go to


Dr Kanako Ishikawa from Lake Biwa Environmental Research Institute, Otsu, Japan, visited Dr Anne D Jungblut (NHM Life Sciences Department) in April 2012 as part of a project supported by a Daiwa Foundation Small Grant that aims to establish a Lake Biwa periphyton species list and carry out public engagement events on biodiversity, management and conservation of Lake Biwa, Japan.



Proliferation of macrophytes and periphyton in Lake Biwa


Lake Biwa is the largest lake in Japan and one of the twenty oldest lakes in the world. It has many endemic species, and supplies 14 million people with drinking water including the megalopolises Osaka, Kyoto and Kobe Cities. It is a breeding ground for freshwater fish and supports commercial fishing.


Microalgae such as cyanobacteria and green algae growing on leaves and stems of submerged water plants (macrophytes) or rock surface are defined as periphyton. These microalgae are not only an important food source for fish and other animals, but can also become nuisance for fishing equipment, water supply system and leisure activities.


Periphyton.jpgPeriphyton collected from Lake Biwa


In recent years macrophytes have become highly abundant in Lake Biwa and as a consequence periphyton growth has dramatically increased. However, little is still known about the species diversity of Lake Biwa periphyton, in particular the presence of non-native and potentially harmful species. During the visit, Kanako Ishikawa and Anne Jungblut carried out DNA-based analyses on periphyton samples collected from Lake Biwa using culture-independent methods.


Lab.jpgKanaka Ishikawa and Anne Jungblut preparing DNA samples for PCR


Anne Jungblut will visit the research laboratory of Dr. Kanako Ishikawa (Lake Biwa Environmental Research Institute) and Dr Taisuke Ohtsuka (Lake Biwa Museum) in Shiga prefecture, Japan, in July.


Steve Brooks from the Museum and collaborators from UCL, the universities of Nottingham, Bergen and Liverpool, and the RSPB have been examining reasons for the breeding success of the Slavonian grebe Podiceps auritus. The Slavonian grebe has a UK breeding population of only 29 pairs, found in NE Scotland only since 1908.  Loch Ruthven holds the largest British population in an RSPB reserve and breeding success is known to have fluctuated annually since records began in 1970.


Slavonian grebe audubon (c) NHM small.jpgSlavonian grebe from Audubon's Birds of America    © Natural History Museum



The research looked at whether the fluctuations are linked to the numbers of chironomids, the group of flies on which Steve is an expert.  These midges are an important food-source for the grebe chicks.


The team analysed a sediment core from the lake by slicing it into 2.5-mm sections to separate sediment on a yearly basis.  In this sediment, they looked at the remains of chironomids, diatoms (planktonic algae which show strong seasonal trends in populations) and algal pigments.   These plant data were used to deduce changes in total phosphorus in the water and to see whether there was a link between algae and the abundance of chironomids. Trends in grebe breeding success, chironomid abundance and algal populations were analysed against climate data to clarify whether climate was the key factor behind all of these fluctuations.


The study shows that grebe breeding success is linked with chironomid abundance and chironomid abundance is linked with total phosphorus. Over the past 100 years, lake productivity and chironomid abundance have both risen, increasing more rapidly from the mid-twentieth century to the present. Fluctuations in grebe breeding success from 1970 followed the same pattern as chironomid variation, with a lag of one year. 


One of the questions of interest was whether grebe breeding success was influenced by climate variability year by year.  Because the Slavonian grebe is a relative newcomer to the UK, it is not clear how vulnerable this small population is to environmental change.  However. No correlation was found between grebe productivity or chironomid abundance and climate.  The team concludes that breeding success of the grebe depends on food availability in the form of chironomids at Loch Ruthven.


Brooks, SJ et al. Population trends in the Slavonian grebe Podiceps  auritus (L.) and Chironomidae (Diptera) at a Scottish loch  Journal of  Paleolimnology April 2012, Volume 47 (4) 631-644  doi: 10.1007/s10933-012-9587-4


David Gower, Mark  Wilkinson, Diego San Mauro (Marie Curie Postdoctoral Fellow),  Emma Sherratt (NERC-funded PhD student) and NHM Scientific Associate S. D. Biju (University of Delhi) collaborated in the discovery and description of a new family of amphibians. 


Chiklidae is a small radiation of caecilian amphibians endemic to northeast India, previously known only from a single poorly preserved specimen collected in 1904. More than a century later this species was rediscoved (and some closely related undescribed species discovered) by the team as a result of the most extensive dedicated field surveys of caecilians that have ever been attempted.


The animals were scanned using Micro CT, and phylogenetic analysis of the relationships of the family within the wider group of caeclians was based on a combination of nuclear genes and complete mitochondrial genomes.  The CT  scanning revealed a distinctive cranial morphology which with the phylogenetic analysis showed the closest relatives to be an endemic African family.


The discovery reveals an ancient Gondwanan biogeographical link between Africa and northeast India.   Gondwana was a landmass that combined South America, Africa, the Indian subcontinent, Antarctica and Australia - the separation of India from Africa began around 120 million years ago during the Jurassic. The breakup of the supercontinent separated populations that diverged in evolutionary terms over time, resulting in new groups of species. (As a parallel example: Humans and the great apes are in the family Hominidae; gibbons are in the closely related family Hylobatidae, although the split between these families is thought to have occurred only 18 million years ago)


This work identifies the first family of vertebrates that are endemic to northeast India and highlights the possibility that northeast India could be a Biodiversity Hotspot - an area of particularly high diversity for many groups of organisms. 


The work was part funded as an International Joint Project (Gower & Biju) of the Royal Society and Indian Department of Science and Technology and has attracted substantial worldwide news media attention.  A video on the discovery posted on YouTube has attracted more than 100,000 hits.


A good slideshow on the Huffington Post

See also:

RG Kamei, D San Mauro, DJ Gower, I Van Bocxlaer, E Sherratt, A Thomas, S Babu, F Bossuyt, M Wilkinson and S. D. Biju. Discovery of a new family of amphibians from northeast India with ancient links to Africa Proc. R. Soc. B doi: 10.1098/rspb.2012.0150

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