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An Indian rust fungus has been released at several sites across England as a form of 'biocontrol' - using a natural enemy to control an invasive species, in this case the Himalayan balsam.


Introduced by Victorians as an ornamental plant, the Environment Agency now estimates that the Himalayan balsam occupies over 13% of river banks in England and Wales. It can reach over 3 metres in height and causes trouble by smothering vegetation, out-competing native plants and by adding to the risk of flooding by clogging waterways.


This week, the not-for-profit organisation CABI released the rust fungus in Berkshire, Cornwall and Middlesex after successful laboratory trials showed that it causes significant damage to Himalayan balsam but does not impact on native species.


The wet Bank Holiday weekend was a wash-out for some, but as Museum botanist Dr Mark Spencer explained, it was the perfect conditions for release: "the fungus does best in warm, wet conditions!"


Know your enemy


Dr Spencer has been advising on the project, which is headed by CABI with primary funding from Defra and the Environment Agency, and with contributions from Network Rail, the Scottish Government and Westcountry Rivers Trust.


Himalayan balsam.jpg

The Himalayan balsam, dominating the banks of the River Alt.

© Mike Pennington


The rust fungus, a natural enemy of the Himalayan balsam in its native lands in the foothills of the Himalayas, has been extensively tested as a natural control method. Conversely, using existing methods, the Environment Agency estimates it would cost up to £300 million to eradicate Himalayan balsam from the UK.


Selection of a suitable natural enemy and laboratory trials took eight years. If the rust is successful in the UK, Dr Spencer predicts it could resolve the problem of Himalayan balsam within a few years.

This is a really important step forward for the control of invasive species in Europe, I wholeheartedly support the decision to approve release. Project partners have already set up a monitoring programme to assess the spread of the fungus onto Himalayan balsam. If the fungus establishes itself at the trial sites there should be no need for additional releases, the fungus will spread naturally through the UK.

The licence to release the rust fungus is only the second of its kind ever issued in the UK, following the 2010 release of a specialist insect, Aphalara itadori, to control the plant Japanese knotweed.


Read more about invasive species in the UK:


A section of the new Infrastructure Bill designed to control invasive species could end up harming important native species such as the barn owl and the red kite.


In an open letter to the UK Government published last week in Nature magazine, 24 leading scientists including Museum researcher Prof Geoff Boxshall called for the bill to be re-written. The letter states that, "If the bill is passed in its present form, it could lead to an irreversible loss of native biodiversity."


The potential problem lies in the way the bill defines a 'non-native' species. According to the letter:

The draft bill defines non-native species as those that are “not ordinarily resident in, or a regular visitor to, Great Britain”. This definition covers past native species that are now extinct, species that may become naturally established under a changing climate, and species listed in Schedule 9 of the Wildlife and Countryside Act.

Schedule 9 contains, among others, several species that have gone extinct in the UK and been reintroduced, such as the barn owl and the capercaillie (a type of grouse).



The barn owl is one species that could have its status changed by the new bill.

© David Tipling Photo Library / The Trustees of the Natural History Museum, London.


The wording of the bill means that species slated for reintroduction, such as the European beaver and wolf, would be classed as non-native and their conservation threatened. Species naturally migrating from Europe as the climate changes, such as butterflies and other insects, would also be punished by the new definition.


Prof Boxshall thinks the definition needs to be changed:

The classification of native versus non-native is an ongoing matter for scientific debate, particularly in the face of climate change. By using such a simplistic definition, the government effectively bars the possibility of reintroduction of locally extinct species and adaptation to climate change.


Amendments have been suggested in the House of Lords to correct the problems in the legislation, but so far these have been rejected.



Some of the earliest mammals had more specialised diets than previously thought, leading to key evolutionary traits we carry today.


Shrew-sized mammals living 200 million years ago in the Jurassic period were thought to be opportunistic insect-eaters with a generalised diet. But a new study by a team of researchers including the Museum's Nature Live science communicator Dr Nick Crumpton shows that two core taxa of early mammals had teeth and jaws adapted to specific kinds of insects.


At this time, small early mammals were known to be evolving the precise chewing and better hearing that are traits of mammals worldwide today. However, it was thought that, because of their general diets, these traits did not evolve in response to different hunting and feeding behaviours.


The new research shows teeth and jaws of early mammals were in fact becoming specialised as a response to different diets.



The Early Jurassic basal mammals, Morganucodon and Kuehneotherium, hunting their prey on the small island they shared in what is now Glamorgan, southern Wales. © John Sibbick.


Dr Crumpton said this gives us new ideas on how the earliest mammals lived:


The idea of the first mammals eking out a meagre living, hiding in the shadows whilst dinosaurs ruled the land is a pervasive one, but we have revealed that even the earliest mammals were already showing specialisations for certain lifestyles.


Tale of the teeth


The team, led by the Universities of Bristol and Leicester, analysed 2cm long jaws and tiny teeth from the mammals Morganucodon and Kuehneotherium found in Glamorgan, South Wales. When the creatures were alive 200 million years ago, the area was made up of small islands in a shallow sea.


Bits and pieces of jaw were scanned and the images stitched together to allow the researchers to determine the bite and strength of the creatures' jaws. This was combined with evidence of 'microwear' on the teeth, patterns of pits and scratches that indicate what the animal was eating.


The patterns on the ancient mammal teeth were compared to those of insect-eating bats alive today that have specialised diets. The combined evidence shows that Morganucodon favoured harder, crunchier food such as beetles, while Kuehneotherium prefered softer prey such as moths and scorpion flies.


Old specimens, new techniques


Dr Crumpton said this research also highlights the importance of specimens that may have been in the collections for decades, but still have stories to tell:


Although our methods were very modern, the fossils themselves had been stored in collections including the Natural History Museum for decades. It's work like this that shows how important museum collections are, and that even though those techniques didn't exist in the 1950s, we were able to study them in fresh new ways in order to discover the secrets they held.



A group of bones discovered ten years ago in Indonesia were determined to be a new human species that lived about 17,000 years ago. The only skull, with very small proportions, earned the species the ‘hobbit’ nickname.


Now, a new paper suggests that the hobbit is just an individual with Down syndrome, but Museum human origins expert Prof Chris Stringer doubts the conclusions.


The find, on the island of Flores, included bones from several individuals, but only one had a complete skull and leg bones, from which the original calculations of height and brain capacity were made.


Standing at approximately 1.06m (3.5ft) tall and with a brain only a third of the size of modern humans, the bones seemed to belong to a new species, which was named Homo floresiensis.



A copy of the Homo floresiensis skull.
Credit: Ghedoghedo, Wikimedia Creative Commons.


A new analysis of the skull and thigh bones, published this week in a paper in the journal Proceedings of the National Academy of Sciences USA (PNAS), suggests that these estimates are too low, and a slightly bigger individual actually lies within the range of modern humans with Down syndrome.


The authors support their claims with other evidence, including the asymmetry of the skull, a condition common in modern individuals with Down syndrome. They conclude this one individual had a developmental disorder, and all the remains were in fact modern humans.


Still a new species?


However, Prof Stringer is sceptical of the conclusions. Although there are no other complete skulls, there is another jaw that has similar proportions and characteristics.


Both appear to have no chin, instead showing internal bony reinforcements similar to those found in prehuman fossils from at least two million years ago. This feature is not found in Down syndrome. The wrist bones of two individuals also show features previously unknown in humans from the last one million years, further indicating a unique species.


Weight of evidence


New human species are often difficult for the scientific community to accept, especially from so few bones. Prof Stringer, however, sees parallels between the stories of H. floresiensis and the Neanderthals, originally described from a single site:

A number of pathological conditions were advanced to explain away the distinctive morphology of the Neander Valley skeleton, but other finds gradually forced the acceptance of the Neanderthals as a distinct and extinct human group.

Prof Stringer acknowledges that more H. floresiensis individuals are needed to establish the range of sizes and shapes there may have been, but he thinks this new analysis does not shake the foundations of the species:

In my view this paper does not provide a sound basis to challenge the basic conclusion that a primitive human-like species persisted on the island of Flores within the last 100,000 years.