Dr Arthur White reports on the rediscovery of a frog in an Indian rainforest, one which has carved out a very un-frog like niche. Only two specimens of the frog were known and the species was presumed extinct. That changed recently when living examples were discovered. The frogs rarely come to ground. The females spawn in multiple tiny hollows in the side of trees, each hollow having some water from the rainforest rains. As the tadpoles develop the mother revisits the hollows and squirts out unfertilised eggs as food. The tadpoles feed on this until they are large enough to metamorphose, a great example of parental care in frogs
Dr Arthur White, President of the NSW Frog and Tadpole Study Group, examines the effects of climate change on Australian frogs and the outlook is not good. Over the last ten years a lot of the climate change models have been continuously refined and the algorithms used today are capable of combining data from diverse sources to produce a unified model. Now the models can predict the effects of climate change on particular areas and can look at changes 50 or 100 or 200 years into the future. Using global models, temperature and rainfall patterns in Australia will change but it won’t be uniform. Some parts of Australia will be being subject to far greater changes, southern Australia being one of the worst areas. This is due not to rising temperatures but to the loss of dependable rainfall, some areas suffering quite badly. Northern Australia will have an increase in temperature but it will also have an increase in rainfall.
Dr Arthur White, President of the NSW Frog and Tadpole Study Group, brings a good news story about the ability of youth to do something positive and scientifically ground-breaking. Recently the prize-winners in the BHP Billiton Science and Engineering Awards were announced and the winner of the category for school students comes on the back of something extraordinary.
Dr Arthur White, from the NSW Frog and Tadpole Study Group (FATS) brings news of a herbicide that affects frogs – atrazine. This chemical is a commonly used herbicide in America and Australia, it being effective and relatively cheap. Atrazine was banned in Europe in 2003 because of the high rates of prostate cancer and breast cancer among people who lived in areas where it had been used. While a lot of it enters plants (it is a herbicide) some of it is washed into creeks, streams and in some cases town drinking water.
Dr Arthur White, President of the NSW Frog and Tadpole Study Group (FATS) looks at the factors that influence the sex determination of frogs, with some surprising information. In the animal kingdom sex reversals as adults are an incredibly common thing unlike mammals and some birds where it rarely occurs. Sex reversal was probably the ancestral condition for all vertebrates, there being advantages to change sex ratios in certain conditions.
Frog ice blocks: Australian desert frogs survive often many months of extreme heat and drought by constructing elaborate systems of tunnels and burrows under the desert floor; and by cutting their metabolic rates and slowing heartbeat of about one beat a minute. However these feats pale in comparison to the extremes endured by the Wood Frog, native to North America, where in this freezing and often frozen environment, there is no food for about eight month of the year. The frog survives even though, anatomical studies show the outer skin and muscles actually freeze. However, the inner core does not freeze thanks to the production of a kind of antifreeze although the heart rate falls to two slow drawn out beats per hour.
The skins of frogs have various antifungal and antibacterial agents, something which has been known since the 15th and 16th Centuries. Dr Arthur White, from the NSW Frog and Tadpole Study Group, explains how frog secretions can form the basis for useful chemical compounds.
Dr Arthur White delves back into frog history and comes up with some surprising information about the early topography of Sydney and the consequent effects of expanding settlement on the native landscape. There used to be at least 20 species - not surprising given that south of the harbour was a wetland wonder.
Dr Arthur White discusses how some Australian frogs adapt to current threats to their environment. As humans continue to alter the landscape, it is logical to think that frogs will be displaced or even die out. While that is true for some species there are, other frogs with specific habitat needs that have managed to survive. This is because they have a capacity to change their requirements when faced with gradual environmental change, such as a slowly drying wetland......gradual change is the key requirement