Herbarium blog

Yams in Madagascar

I have recently become involved in Kew’s long-running project studying Yams in Madagascar.

Yams are important to many rural communities in Madagascar. Collecting wild yams from the forest provides a food source during the months when rice is unavailable or prohibitively expensive. At least 30 of the 40 yam species found on Madagascar are edible. From a conservation perspective, Madagascar’s 40 species of yams are especially precious as they only grow naturally in Madagascar and some species are particularly rare. Many of Madagascar’s yam species are narrow endemics, being restricted to a small area, and 12 of them are provisionally considered threatened. All the yam species shown to be threatened are edible. For example,  bako (Dioscorea bako) has been classified as Endangered and may be suffering from over-utilisation.

An inhabitant of the village of Beroboka in western Madagascar carrying Dioscorea bako tubers (Image: A. & M. Hladik)

Kew's work in rural communities

Kew is working with a charity based in Madagascar called Feedback Madagascar. Amongst other projects, Feedback Madagascar and Kew are collaborating to promote yam cultivation in rural villages. By increasing the numbers of cultivated yams, the aim is to reduce the pressure on wild yam populations from over-extraction and associated habitat destruction. Such cultivation of yams could also improve food security in these rural communities.

I will be travelling to Madagascar in May 2012 to visit some of the villages that have started to cultivate yams. I will be collaborating with Feedback Madagascar to survey villagers and see if they prefer cultivated yams over those that can be collected from the wild. This work is supported by both the Bentham-Moxon Trust and Kew Guild. I have been trying out parts of the survey in advance on colleagues at Kew!
 

A Madagascan yam tuber from the species Dioscorea arcutinervis

We hope that the survey in May will show which wild or cultivated yams are most favoured as foods in a group of rural villages and what scope there may be for cultivated yams becoming a locally tradeable food. An estimation of the value to a rural community of wild yams collected from a thriving forest may also be useful to local decision makers when deciding whether forest should be converted into fields or not.

- Tim -
 

Related Links

• Explore the e-monocot pages for Dioscoreaceae
• Explore Dioscoreaceae  on The Plant List
• Innocent Foundation support for Madagascan yam cultivation project
• Find out more about the yam Dioscorea bako

Botany, fungi, algae and nomenclature are sometimes seen as the dull and conservative corner of the biological sciences. But botanists were anything but boring this summer in Melbourne, where some revolutionary decisions were made by the ca. 200 people attending the Nomenclature Section of the Eighteenth International Botanical Congress, 18-22 July 2011.

Rules governing names are modernised

Getting your plant names right is a complicated business. In order for Rosa canina L. to be a correct Latin binomial, fit for use in your garden, the name must be effectively published, validly published, legitimate, and the earliest name to be published for this species (terms in the Zoological Code are a bit different, but the idea is the same). In finding the right name, all relevant literature published since 1753 must be considered - often a lengthy piece of detective work in the archives. The International Code of Botanical Nomenclature (ICBN) is a set of rules and recommendations recognised since the “Vienna Rules” of 1905, and amended every six years by the Nomenclature Section, a five day meeting organised by the International Association for Plant Taxonomy (IAPT) and held a week before the much larger International Botanical Congress (www.ibc2011.com). Institutional representatives carry institutional votes and each person present carries a personal vote. Proposals to amend the code are compiled by the Rapporteurs after publication in the journal Taxon, sent out to all IAPT members in a mail vote, then discussed and voted on in the Nomenclature Section following approval by the mail vote; propositions from the floor can also be discussed.

Latin is no longer required to describe new species

Plant habitats are disappearing every day but it is estimated that around 20% of plant species have not even been described yet. Undiscovered biodiversity is mostly in understudied places, like the tropics, and understudied groups, such as large genera, many of which are already available in our herbaria but not yet assessed by taxonomists. Describing new species needs careful evaluation of taxon boundaries. Many people do not realise that in order to describe a new plant species in 2011 one must also write a short description in Latin.

As a graduate student I spent hours surrounded by ancient dictionaries trying to get the ablative plural adjectival endings correct, in agreement with the nouns and also in agreement with the botanical Latin tradition, not always the same as classical Latin. It was challenging for me, but what about all the people who do not have access to botanical libraries? And people who do not speak a Romance language? Latin was the international scholar’s language made compulsory to make descriptions understandable to people who did not speak the publication language. Proposals to drop the requirement for Latin have been considered in almost every Nomenclature Section meeting to date, and to many people’s surprise, this time the result was “yes”. From 1 January 2012 English will be accepted as an alternative to Latin. It has been pointed out that the Church of England permitted an English language Bible almost 500 years ago in 1539. But do not throw away your copy of William Stearn’s Botanical Latin just yet. This change only applies to describing new taxa. The name Rosa canina is still in Latin and follows Latin language rules: the gender of the adjectival epithet has to agree with the gender of the generic name. And much of the accumulated literature will remain in Latin.

New plant names can be published online

It is not always easy to connect a plant to its name. When a new species is described the name enters the pool of available names. The name is recorded by an indexing service: the International Plant Name Index (IPNI) for vascular plants, Tropicos (http://www.tropicos.org/Home.aspx) for bryophytes, AlgaeBase and Index Nominum Algarum for algae, and Index Fungorum for fungi. This description will likely be consulted by each future taxonomist revising the group. Many people are worried about the possible loss of species descriptions and until now at least two copies of the publication have been required to be deposited in libraries. Following many years of discussion on digital formats, secure storage media, and data accessibility, a vote was taken and paper copies are no longer required. From 1 January 2012 a new plant name may be published online as a PDF (or successor format), as long as the online publication has an International Standard Serial Number (ISSN) or an International Standard Book Number (ISBN). Preliminary versions or later corrections are not accepted.

Register your mushrooms

New names of fungi must now be registered in a recognised name repository such as MycoBank and a unique identifier will be issued by the repository and included in the publication. This ensures that the international community is aware of all newly published names, and that information on the new taxa is made available. Such a system of name registration has also been proposed for animal names (via ZooBank), and may eventually be introduced for plants, although there are worries that this limits the freedom of independent researchers. Following an additional amendment widely used names of fungi will also be fixed and protected from change.

One name to cover all life stages of a fungus

Sexual and asexual forms of a fungus can look very different to each other and it is not possible to establish that they are the same organism without using molecular technology. These different forms have been described under different names, meaning that one species of fungus could have one name for its sexual state, and one name for its asexual state. Now that the molecular technology is more broadly available this awkward situation is no longer permitted, and one species of fungus can only have one correct name, the name that was published first.

More flexibility and fewer kinds of names for plant fossils

The situation with the names of fossils is even more complex than with fungi because individual parts of an organism are often preserved separately in the fossil record. One organ of one species can look different depending on its life stage and history of preservation. Researchers build hypotheses as to which fossils belong to one original organism, but unlike the situation with fungi the hypotheses remain uncertain due to lack of information, and there is insufficient confidence to synonymise all the separate names (fossil plant names and the discussion are explained by Cleal & Thomas in Taxon). Individual parts of theoretical assemblages were called “morphotaxa” and these have now been disallowed to give greater flexibility. It is hoped that these changes will make it easier for the palaeobotanists to correctly follow the naming rules.

When is an acacia not Acacia?

Research has demonstrated that the trees and shrubs traditionally known by the generic name Acacia are in fact two separate evolutionary lineages. Australian Wattles are not the closest relatives of the iconic African (and Central and South American) acacia trees, so the two groups need to have different Latin generic names. Changing Latin names is confusing, expensive, and generally undesirable but the naming system exists to reflect evolutionary history as well as providing useful unique identifiers. Only one group can retain the Latin generic name “Acacia”. But which group? Australian acacias have a larger number of species, but African acacias have a great ecological significance in African savanna. According to the rules, each genus has one type species, in this case the African Acacia nilotica, and the generic name stays with the type species. The type species was changed to the Australian Acacia penninervis at the 2005 International Botanical Congress, held in Vienna, in order to decrease the total number of name changes. The debate continued long after the Vienna Congress and several compromise proposals were made to the Nomenclature Section in Melbourne, including a proposal to allow the name Acacia to be used for both groups, and a proposal to change the names of both groups. The Nomenclature Section voted to uphold the decisions taken in Vienna in 2005 and the Latin generic name Acacia will be applied only to the Australian plants (further explanation here). Of course this only concerns the formal Latin names and the use of the vernacular name acacia is not controlled by the Code.

ICBN transforms into ICNAFP - the International Code of Nomenclature for algae, fungi, and plants

This may have been the most revolutionary Nomenclature Section ever held, a fact also reflected in a change of title. An unexpected proposal from the floor suggested amending the title of the Code, and it is hoped that this change will clarify which groups are governed by the Code, and help keep the rules for algae, fungi, and plants united under the same Code – recent understanding of higher level eukaryote relationships has shown that fungi and most algae are not closely related to plants. The word “organism” instead of “plant” will be used throughout to reflect the inclusion of algae, fungi, and plant fossils. The fact that fungal and algal names are regulated by the botanical code is a historic anomaly dating back to the days when fungi and algae were considered to be plants, but moving across to another set of rules is not really possible because the naming system needs to remain stable. It has been suggested that decisions on fungal names could be made at the International Mycological Congress (IMC) but this may prove difficult due to the lack of an established representation and voting system like the one at the Botanical Congresses. A Special Committee concerned with governance has been set up to explore these and other issues and report to the next Congress. Other decisions will also have an appreciable effect on the daily work of a taxonomic botanist. A new Appendix will be added to the Code to list decisions on which names are considered sufficiently different to be unambiguously distinguishable (if two generic names or two species in the same genus differ only by a minor spelling variation, one of them must be changed). The Editorial Committee may decide to publish the Appendices (including lists of approved and rejected names) separately from the Code itself, putting an end to the traditional thick volume, printed after every Congress, which has been getting thicker and thicker.

What about non-plants?

Separate communities of specialists have traditionally made decisions about different groups of organisms (explained by Knapp et al. in this article). The International Commission on Zoological Nomenclature (ICZN, or the Zoological Code) looks after Latin binomial names of animals, with some historic exceptions among problematic metazoans and Protists (binomial means having two names, a generic name and a species epithet). The International Code of Nomenclature of Bacteria (the Bacteriological Code) looks after Latin binominal names of bacteria. Other sets of rules govern names that are not binomial (The International Code of Virus Classification and Nomenclature; International Code of Nomenclature for Cultivated Plants; International Standards for Naming Pathovars of Phytopathogenic Bacteria). Cross disciplinary work by the International Committee on Bionomenclature (ICB) has produced the Draft Biocode 2011, bringing together the different sets of rules for binomial names and drawing up guidelines to apply across the Codes. Some people support the development of an overarching Biocode, but others do not like the idea of another set of rules on top of the special Codes already in use. Nomenclature is a historic discipline rich in local idiosyncrasies. Democratic independence of the separate communities is important to maintain. Would the Biocode just add complexity to what is already a confusing specialist discipline? Or should we all work together to make one united system? Join the discussion! 

- Maria -

The Cerrado savannas of central Brazil, sometimes known as the ‘Amazon’s forgotten cousin’, are being destroyed at an alarming rate. Tremendously important for their biodiversity and the ecosystem services they provide, these fragile habitats are being cleared wholesale for agriculture – particularly for soya production.

Kew is collaborating with the Royal Botanic Garden Edinburgh and WWF in a programme designed to raise the profile of the Cerrado, increase public awareness of the importance of its conservation, and inform consumers of the potential impact of their food consumption.

The video footage of the Cerrado shown in this film by the Forgotten Forests project, run by the Royal Botanic Garden Edinburgh, was shot by Kew's Tropical America Team during a recent expedition to Brazil.
 

Related links

• Kew's Tropical America Research Programme
• WWF Save the Cerrado
• Conservation and management of the Cerrado
• Royal Botanic Garden Edinburgh's Forgotten Forests page   

Science & Conservation at Kew

This week 16 participants from seven different countries arrived at Kew’s Herbarium for the annual Tropical Plant Identification course. Organised by myself and Tim Utteridge, the course is aimed at people such as botanists, ecologists and conservation workers, who need to identify tropical plants either in a herbarium or during fieldwork. This year we are teaching colleagues from other botanic gardens in Singapore and Canada, botanists from Papua New Guinea, Indonesia, Malaysia, Madagascar and Namibia, as well as an ecologist and museum curators from the UK, and Kew staff.

Learning from specimens during the ID course

 

Over an intensive two weeks of lectures and practical sessions, 21 of Kew’s botanists will teach the key combinations of characters that will enable the course participants to identify c. 60 tropical plant families. That’s a lot of information to remember! We will use the dried specimens from Kew’s herbarium to practise spotting key characters, and arrange special ‘family sorts’ focused on plant families from different tropical regions of the world. And we will escape into the gardens where we will see whether what we have learnt using dried specimens works with living plants!

Looking for key characters for Annonaceae, Myristicaceae and Lauraceae using herbarium specimens

At the end of each week there will be an identification test – we’ll hide the name of each specimen, and each participant will have to name the plant family the specimen belongs to. This might sound mean, but this ‘botanical challenge’ is an informal way to make sure we know how well we have been teaching identification skills. Fingers crossed everyone gets 100% this year!

The Tropical Plant ID course is just one of many courses taught by Kew staff, for more information see the ‘Learn’ section of the website.
 

- Gemma -

NB - This is a silent film.  

 [Incorporating footage by W. Milliken and Alex Forte]

- William -

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