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Many species and larger taxonomic groups, especially invertebrates, have been little studied in terms of their patterns of geographical distribution - biogeography - and even basic information, inventories and assessments are missing.  A key reason for this is that collecting and sampling has been too limited and too uneven: there are simply no good baseline data on distributions.


Ian Kitching of the NHM Life Sciences Department, with colleagues from the University of Basel, Switzerland, and Yale University, USA, set out to establish why inventories for the hawkmoths of Sub-Saharan Africa are incomplete, considering human geographical and associated environmental factors.


Xanthopan morganii praedicta - a hawkmoth found in Madagascar and East Africa


They used a database of hawkmoth distribution records to estimate species richness across 200 x 200 km map grid cells and then used mathematical models predict species richness and  map region-wide diversity patterns. Next, they estimated cell-wide inventory completeness related to human geographical factors.


They found that the observed patterns of hawkmoth species richness are strongly determined by the number of available records in grid cells. Vegetation type is an important factor in estimated total richness, together with heat, energy availability and topography. Their model identified three centres of diversity: Cameroon coastal mountains, and the northern and southern East African mountain areas. Species richness is still under-recorded in the western Congo Basin and in southern Tanzania/Mozambique.


What does this mean?  It means that sampling (and therefore our knowledge) of biodiversity is heavily biased.  We have good data and information where there is higher population density; for more accessible and less remote areas; for protected areas and for certain areas where there was collecting in colonial periods.  If it is easy to get to, not too difficult to access, there are more people around and there have been longer histories of collecting: we have better knowledge. 


This is important in how we understand biodiversity and in how we make decisions with our knowledge to protect forests or other areas.  But this study means that we can take account of data gaps if we are looking at larger scale patterns of diversity.  It shows that baselines for broad diversity patterns can be developed using models and what data there is available.  We can identify the "known unknowns" in terms of information gaps in part by looking at human geographical features - the models can help set priorities for future exploration and collection as well as informing our understanding of biodiveristy.

Ballesteros-Mejia, L., Kitching, I.J., Jetz, W., Nagel, P. & Beck, J. 2013. Mapping the biodiversity of tropical insects: species richness and inventory completeness of African sphingid moths. Global Ecology & Biogeography 22: 586-595. (doi: 10.1111/geb.12039)


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


Back to town, paperwork awaits. We have to sign the final Material Transfer Agreement to allow me to take our specimens out of Tanzania tomorrow. This is not my favourite part, I would much rather be back in the cloud forest. Sorting collections, using the herbarium to identify what we collected, making sure everything is fully dry, and separating the collections into the set that will stay at the University of Dar es Salaam and other sets to go to the Natural History Museum London and the University of Utah. It has been an amazing trip!




My boots have just dried out from Ruvu forest, but they didnt stay dry for long. Another drenched soaking wet day today.


We climbed up Chensema in the rain inside a cloud, and tried to find our target species in the cloud forest at 2100 m elevation. The dripping wet grass and shrubs made it difficult to move forward, the paths were narrow, and everything was washed out and slippery. Steep paths up to the forest were the worst.


Usually the paths are raised and narrow, just wide enough for one foot. When the rain starts it is impossible to step without slipping. I was worried about going down that path and falling.


We were several hours away from a road and getting help would have been difficult. Eventually we gave up and returned early. The cloud forest just is not passable in this weather, and we had been wet and tired for many hours.



Inside a cloud in the Uluguru cloud forest – it is not possible to see anything very much and it is difficult to move forward in this vegetation.


We got soaked to the skin and carried on walking through rice fields for many hours. I put my belongings in plastic bags, inside other plastic bags, but the papers and my notebook still got wet. It was a warm and pleasant temperature but everything was totally drenched, and my boots were full of water all day, and we didnt have any food. We were back in Ruvu Forest, making another attempt to find the new Solanum species that may be extinct. We reached the place where it was originally collected in 2001. This turned out to be a dense thicket of spiny lianas climbing over strange-shaped limestone rocks, the only place unsuitable for cultivation and so not cleared for farming. I spent a while climbing inside it looking for the Solanum. It wasnt there, but I found a stinging liana instead, and I now have large red welts all over my arms - would be interesting to know what species it was. We got lost in the mixed mosaic cultivation of rice, maize, and sesame, in spite of walking with several local guides. Our car got stuck in the mud and had to be pushed out by numerous local villagers. I was very relieved when we were back on the tarmac road. All the streams swelled during the day and if we could not get out of there, we would have had to spend the night in the forest and order a tractor to pull us out tomorrow.



Eric and I are soaked to the skin, trying to shelter from the rain in a small farmer’s hut. The roof was leaking and the rain showed no sign of stopping, so we had to carry on going.


pic2-rainy-season-road.jpgFinally back on the main road! These roads become completely impassable when the rainy season starts properly, and we were lucky to get out of there without getting seriously stuck.



Dry savanna. Our car is parked by the side of the road.


We drove for almost 15 hours today, from Korogwe in the north to Mbeya in the south. Spectacular landscapes. It was cold and wet, then dry and hot, then gradually colder again as the elevation increased heading south. We almost got seriously stuck between Korogwe and Morogoro because a lorry turned over blocking the road so no vehicle could pass. This is the only tarmac road connecting the north and the centre of Tanzania and so much traffic was building up on both sides of the accident the emergency services could not get through. Local villagers were charging money for letting cars drive around the blockage through their village, and we managed get around and avoid getting stuck.


Mostly recovering from yesterday. My legs hurt, my arms hurt, my appetite is coming back.. Because of yesterday’s success we decided to move north earlier, so the day was spent driving up to Tanga. Solanum dasyphyllum is planted by farmers near their houses to keep away the ants in this area – you cant find out this kind of information by looking at specimens in a museum!



Farm where Solanum dasyphyllum is planted to keep away ants. Colleagues Frank Mbago and Eric Tepe are at the front of the picture.



Me pressing a specimen of the Uluguru Mountain endemic Solanum inaequiradians


Today was very intense! We found Solanum dasyphyllum (growing in mountains all over Africa, with large and wide spiny leaves), Solanum stipitatostellatum (Tanzanian endemic with many curved spines, sterile), Solanum inaequiradians (Uluguru endemic never discovered on this mountain before, with long thread-like calyx lobes), Solanum schliebenii (very rare endemic with bizzare floppy bristles on the stem, we were hunting for it all day), and Solanum aethiopicum (the Scarlett Eggplant, commonly cultivated for food). We walked from 9pm to 7pm in 35 degrees C, up a steep slope, and I dont feel so great now. There are no roads up to the Tegetero forest and local villagers go up a narrow steep trail for many hours carrying bananas to the market. I fell down a slippery slope in the forest, and rolled downhill for about 5 metres, luckily it was soft and all I have is a few cuts. I would like to write more but I am too tired.



Tegetero forest: we walked all the way up here!



long with Darwin's 200th birthday celebrations, 150 years since the publication of On the Origin of Species and the International Year of Astronomy (marking 400 years since Galileo first looked up at the sky through a telescope).....2009 is also Year of the Gorilla. 


To help celebrate Year of the Gorilla, we held an event with tropical biologist Ian Redmond last Tuesday. Ian is a well known figure in the world of gorilla and great ape conservation and speaks passionately about the plight of gorillas and the forests they live in. This year, he travelled to 8 of the 10 countries where gorillas are still found in the wild and wrote a blog as he went.  He also filmed the people he met and recorded interviews with government officials, bushmeat traders and park wardens amongst others. To find out more, visit the Year of the Gorilla website





Following Lucy’s blog post about the discovery of new Solanum species in Kenya by Drs Maria Vorontsova and Dr Maarten Christenhusz earlier this year, I’ve had the opportunity to catch up with Maria to find out more about why they made the visit and the implications of their findings.


Maria tells me that her interest was first piqued when she was studying herbarium specimens of African Solanum in the Kew Gardens herbarium collection. She says she saw some strange specimens that didn’t have species names and didn’t look like any other species. Intrigued, she recorded locality information from the labels to find out where they were from. She then travelled to Kenya to see if the plants were still there and to find out if they really were new species like she suspected.


  Maarten and Maria working in the field


Visiting old collection localities, Maria and Maarten found that in many places there was no more native vegetation because the goats ate everything, and in other places because there was now a maize plantation there instead.


Nonetheless, their four weeks spent hunting for Solanum paid off as they identified three new species - Solanum polhillii (which is named after the brilliant botanist Roger Polhill), Solanum phoxocarpum (which means ‘pointy fruited’) and Solanum malindiense (which means that the species comes from Malindi). Maria and Maarten are now writing a journal article describing the new species.



Solanum malindiense


They saw severe habitat degradation for two of the species and the trip has highlighted how rare species are disappearing before we even know they are out there.


A lot more work is needed, says Maria. In her words: ‘There are so many strange and beautiful tropical plants out there, and we don’t even know how many species we have.’


She added that as long as we don’t know how many and what species there are, we can’t know how to protect them or what useful resources they might provide.


It’s a big task, but scientists from the Botany Department are doing what they can to rectify this situation. The Museum is part of Solanaceae Source, a worldwide collaboration to study the genus Solanum. Most of the 1500 known species in this large genus grow in South and Central America, while Tanzania and Kenya have the largest diversity of spiny Solanums in Africa.


So what’s next? As well as preparing the journal article, Maria is now working towards a book on all spiny Solanum in Africa and Madagascar and is planning to go to Tanzania and Madagascar in 2010. Let’s hope we can catch up with her again then.