Australasian Science: Australia's authority on science since 1938

Browse Briefs

By Stephen Luntz

Brief bites of science news for subscribers only.

Fly Is Bootylicious
Many biologists hope for immortality by naming a species after themselves, but Bryan Lessard of CSIRO Ecosystem Sciences has packed his fame into a smaller space of time, winning notoriety by naming a fly after pop singer Beyoncé Knowles.

Scaptia (Plinthina) beyonceae is a horse fly that reminded Lessard of the singer’s hit, Bootylicious. “It was the unique dense golden hairs on the fly’s abdomen that led me to name this fly in honour of the performer Beyoncé as well as giving me the chance to demonstrate the fun side of taxonomy – the naming of species,” Lessard said.

The fly was first collected in 1981, the year Beyoncé was born, but the shortage of taxonomists meant that Scaptia species have sat undescribed for decades. More than 4000 species of horse fly have been collected worldwide, and Lessard said: “Although often considered a pest, many species of horse fly are extremely important pollinators of many plants.” All three known specimens are female.

Warm-Ups Too Long
Professional sporting clubs are using unnecessarily long warm-ups for their players before games, sapping their stamina during the match itself.

The Journal of Science and Sport Medicine has published a comparison of 6-minute and 23-minute pre-game routines, and found that players were faster, more agile and jumped higher with the shorter routine. “This shows that beyond the 5 minutes needed to increase heart rate and muscle temperature, then a couple of targeted explosive routines, you can just start tiring players out for no real benefit,” said PhD student James Zois of Victoria University’s Institute of Sport Exercise.

The benefits were as large as 7%, but Zois noted that players with injuries might need extra stretching or other preparation prior to games.

Side-effect Struggle
A combination of metabolic screening and advice on diet and lifestyle is being promoted to counter the side-effects of anti-psychotic drugs.

Drugs that are used against bipolar disorder and schizophrenia often have side-effects that can shorten life expectancy significantly. “As an endocrinologist, I regularly see the effects of metabolic syndrome and poorly controlled diabetes. These include kidney failure and amputation, tragedies we desperately wish to avoid,” said A/Prof Katherine Samaras of the Garvan Institute.

Samaras notes that people with psychosis have a life expectancy 20 years lower than the rest of the population, with diabetes often implicated in their deaths. She is an author of a paper published in Early Intervention in Psychiatry that sets out how physical interventions can accompany psychiatric ones.

Termites Sound Warning
An acoustic device that detects the sound waves produced from termites chewing can reliably detect infestations early, according to Edith Cowan University researchers. Upon detection of the vibrations, the wireless smart probe, WiSPr, sends a message to a pest control company.

“It’s a wireless acoustic sensor that listens and recognises the acoustic ‘signature’ of termites chewing on your house,” says A/Prof Adam Osseiran. “You would need about 20 devices placed every few metres around a house, and they would be continuously listening and monitoring and providing an effective shield against termite attacks.”

Any termites detected have only themselves to blame, as smaller termites use the vibrations caused by their larger rivals to avoid encounters (AS, October 2009, p. 11).

Going Bananas for Light
Bananas base their development on the length of light they receive rather than on temperature, as previously thought. Prof David Turner of the University of WA has reported in Functional Plant Biology that long periods of sunlight during the mid-vegetative stage increased the appearance of bunches 8–10 weeks later.

“Originally we thought the development of bananas wouldn’t be responsive to photoperiod but there’s some literature that says temperature isn’t the only thing that explains it,” Turner says. “Once we got into the numbers we were surprised that the message seemed to be so clear across all locations.”

The results may be used to enable breeders to select banana plants that are either more or less sensitive to the length of sunlight in order to maximise production in different conditions. An experiment has begun on the use of artificial light.

Schistosoma Sequenced
The genetic code of the parasite Schistosoma haematobium has been sequenced, and priority drug targets identified.

Schistomiasis is considered one of the developing world’s most devastating diseases, causing bladder cancer and increasing the transmission of HIV. The parasite is spread by snails, and can be acquired by drinking or bathing in infested water. Two related parasites associated with intestinal and liver disease have also been sequenced.

Dr Neil Young of the University of Melbourne’s School of Veterinary Science, one of the lead researchers in the international project, said: “This genome was the missing piece of a puzzle in schistosomiasis research. By revealing the genetic blueprint of Schistosoma haematobium, we now have a biological road map of the three major parasite species responsible for human schistosomiasis globally. Most importantly, the genome of Schistosoma haematobium will offer insights into how the intimate relationship between a parasite and its human host can induce malignant bladder cancer.”

The results of the study were published in Nature Genetics.

Calorie Counting Key
The most effective way for people who are both overweight and have type 2 diabetes to lose weight is to reduce their total calorie intake rather than observing fad diets, according to a study by Dr Jeremy Krebs of the University of Otago.

“We decided to do this study as weight loss is very important in terms of control of blood sugar levels, and many people with diabetes are seriously overweight. However, there has been a lot of medical and public debate about the best way to achieve this, and which diets may be the most effective over the long term,” Krebs said.

In Diabetologia, Krebs published a study of 419 New Zealanders with diabetes and BMIs over 27. On average, those participating lost 2–3 kg, and there was no significant difference whether they used a low fat/high protein diet or a low fat/high carbohydrate diet.

Krebs notes that 30% of the participants in his study dropped out because they could not stick to a specific diet, and others struggled to reach the proportion of particular foods prescribed. Overall calorie limitation, while hard, allows individuals a choice of the foods that suit them best.

Tea Tree Oil Stops Flystrike
Tea tree oil could provide a simple answer to flystrike and louse infestation, something which costs the Australian sheep industry $400 million per year. The oil of Melaleuca alternifolia is a natural medicine to indigenous Australians, and has become a popular folk remedy for wound healing and as an insecticide, but scientific confirmation is new.

“In scientific trials we’ve demonstrated that lice were eradicated from sheep dipped in diluted tea tree oil, using concentrations of 1–2%,” said Dr Peter James of the Queensland Alliance for Agriculture and Food Innovation. “Our sheep trials confirmed our work in the laboratory, which suggested that a 1% tea tree oil formulation could kill both lice and their eggs.”

With resistance growing to existing pesticides, and concerns about the health implications of some farm chemicals, tea tree oil could prove valuable, although James warns: “It’s not as simple as mixing tea tree oil with water and applying it to your sheep; it’s a complex and exact science.”

Jellyfish Not Rising
Reports that jellyfish numbers are on the increase are unsupported, according to a paper in BioScience.

A number of recent reports of large jellyfish outbreaks have come with claims of a global trend attributed to the removal of predators or global warming. However, Prof Carlos Duarte of the Ocean Institute at the University of WA said: “After examining the evidence, we believe that claims of a big rise in jellyfish numbers is very much a case of misreporting of qualified data.”

Jellyfish numbers do appear to be increasing in some areas, for example around Japan. However, in other regions fluctuations have been reported as a trend, often as a result of single dramatic events, such as the world’s largest nuclear powered ship, the USS Ronald Reagan, withdrawing from Brisbane Harbour after jellyfish blocked the intake valves.

Duarte is using a newly constructed database of 500,000 jellyfish records dating back to 1750 to seek evidence of previous blooms.

Black Hole Sheds Light on Galaxy Creation
A newly discovered type of black hole – an intermediate mass black hole – can help us understand how galaxies are formed, according to Dr Sean Farrell of the University of Sydney. The research, published in the Astrophysical Journal, examines how these intermediate mass black holes form, and in turn the formation of galaxy creation.

In 2009 a team led by Dr Farrell discovered the first intermediate mass black hole, called HLX-1, which Farrell says is about 20,000 times the size of our Sun. “Our latest finding is that we’ve detected evidence for a very young massive cluster of stars around the HLX-1 black hole,” Farrell says. “The fact that it’s a very young cluster of stars indicates that our intermediate mass black hole may have originated as the central black hole in a very low mass dwarf galaxy that has been swallowed by the massive galaxy that it now resides in.

“This has really important implications for how supermassive black holes form, and therefore how galaxies form and evolve. Before this we had very strong evidence for the existence of intermediate mass black holes, but we weren't sure where they were formed. Now we may be able to understand where they come from.”

The formation of stellar mass black holes through the collapse of massive stars is well accepted, but it is not yet completely clear how the supermassive black holes are formed.

“Supermassive black holes may form through the merger of intermediate mass black holes, so studying intermediate mass black holes and the environments in which they are found has important implications for a wide range of important questions in modern astrophysics,” Farrell said.

“Intermediate mass black holes are a crucial missing link between stellar mass and supermassive black holes, and may turn out to be the building blocks of the supermassive black holes found in the centres of galaxies. Our own Milky Way galaxy may be filled with them.”