June 28, 2009
An interesting study from researchers at Auckland University suggests that molecular evolution happens faster in warmer climates. This in itself is not a novel finding, as the relationship has been found previously for ectothermic organisms -“cold-blooded” organisms whose body temperature is directly linked to climate. What makes this new study interesting however is that this relationship also appears to hold for warm-blooded animals. Because warm-blooded animals regulate their own body temperature, it was previously assumed that rates of genetic change in these organisms would be independent of climate.
The study measured the rate of evolution at a mitochondrial gene (cytochrome b) in 130 pairs of mammalian species, where one species in the pair occurs at lower latitude or elevation (warmer climate), and the other occurs at higher latitude (cooler climate). The rate of evolution was about 1.5 times higher in species found in warmer climates, and the results held even when the effect of differences in body size or population size were taken into account. Of course this study only used one mitochondrial gene (probably because of the availability of data for this gene across a wide range of species), and there are many reasons why what goes on in the mitochondria might not be the same as what goes on in the rest of the genome, particularly for factors likely to be associated with metabolic rate. So we can’t really say that species in the tropics are evolving faster on the basis of this result. But it will be interesting to see if this relationship holds across the rest of the genome.
The study has just been published online in Proceedings of the Royal Society London B – see more about it here. And the original paper here
June 27, 2009
Just saw this on Scepticon, via Open Parachute:
Just a quick post to spread the word about a survey covering the public acceptance of evolution in New Zealand and the effect (if any) of religious/spiritual beliefs on the the extent to which evolution is accepted in the wider community. The survey can be found Here, and the results will be presented around November 2009.
The survey is being conducted by Drs Marc Wilson and Peter Ritchie of Victoria University in Wellington. I hope to secure an interview with the two Drs closer to the release of the data to get their views on the implication of the findings. In the mean time go participate in the survey, it will only take a few minutes and will be time well spent.
I”m looking forward to see the results of the survey – are creationist beliefs as pervasive here as they are in the US? Somehow I doubt it, but it will be interesting to see the results.
June 24, 2009
Conservation management in New Zealand often involves translocating endangered species to predator-free sanctuaries. These translocations are often not as successful as they should be, but it can be difficult to pinpoint the reason why. A major problem for newly established populations can be the loss of genetic diversity that comes with establishing new populations from only a few founders. Loss of genetic diversity can increase the risk of extinction by reducing a population’s ability to adapt to new threats or environmental changes. Generally, conservation management programs for threatened species should aim to retain 90-95% heterozygosity over 100-200 years, but in reality management practices are often dictated more by convenience or by what can be realistically achieved in the field at the time.
Tuatara ready for release
New research (to be published soon in Molecular Ecology) by Victoria University PhD student Kim Miller has the potential to improve translocation planning for our native reptiles by offering guidelines for maximising genetic diversity and managing populations over time. Read the rest of this entry »
June 20, 2009
Since I became interested in science blogging a few months ago, I’ve been wondering how many other New Zealand-based science blogs there are out there. So I endeavoured to compile a list. Straight away I ran into the issue of how to define a science blog – should it just be restricted to a blog about science written by a scientist? Where do you draw the line between blogs about natural history or the environment and blogs about science? In the end I decided that a science blog should be mostly made up of posts about peer-reviewed science – this includes posts about the research itself, political/cultural issues surrounding research, and science communication. Most of the ones below are written by scientists (but not all)
Read the rest of this entry »
June 16, 2009
Swine flu is at the forefront of the news again, so it is timely that an analysis of the origins of the virus has now been published online in Nature. A team of researchers from the UK, Hong Kong and the US used evolutionary analysis to reconstruct how and when this strain of the virus (which is now referred to as swine-origin influenza-A (H1N1) virus, or S-OIV) developed. By comparing the genome sequences of the pandemic strain with 100s of other strains from pigs, birds and humans that represent the full spectrum of influenza A viruses, the team was able to build a family tree of S-OIV and date its emergence.
Their analysis shows that S-OIV is derived from several viruses already circulating in pigs, some of which were originally of avian or human origin. The initial transmission of S-OIV to humans occurred several months before the outbreak was recognised. Read the rest of this entry »
June 12, 2009
Some new initiatives in science communication have been suggested in an article in Nature Biotechnology this week. The article is based on a science communication workshop that was held in Washington DC earlier this year, and one of the authors, Matthew Nisbet, has a run-down of it on his blog Framing Science – see here.
The eight main recommendations of the article are… Read the rest of this entry »
June 10, 2009
I’ve decided to start a couple of monthly series, in order to keep this blog on track and create a few themes. Photo of the month is quite obvious, but the “rules” are that it will be an native species from the NZ forest, in its natural environment*.
For this month, here is a northern rata flower (Metrosideros robusta) to remind you of summer. Taken on the slopes of Mt Kapakapanui in the western Tararua ranges, just north of Wellington. Interesting that the flower was quite yellowish instead of red – can any botanists out there shed some light on why this is?
*Rules may be subject to change