Tuatara tuesday – sex determination in a warming world

November 9, 2010
Seeing as reptile reproduction seems to be a bit of a hot topic right now, I thought it was time to talk about sex determination in tuatara.

Tuatara do things a little differently to other reptiles when it comes to sex determination – not because they have temperature-dependent sex determination (thats common to lots of reptiles), but because their pattern of temperature-dependent sex determination (or TSD) is different from most other reptiles.  For tuatara, incubating eggs at higher temperatures (over 22°C) produces males, while lower temperatures (under 21°C) produce females.  In other reptiles with TSD, you generally either get a pattern of females being produced at high temperatures and males at low temperatures, or females being produced at both high and low temperatures, and males produced at intermediate temperatures.

Tuatara hatchling

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From the Herald: Climate debate adrift on rising tide of lunacy

August 14, 2009

I wasn’t planning to write about climate change on this blog, as I don’t know much about the science and hot-topic does an excellent job of it already.  However, I wanted to re-post some of this opinion piece from the Herald, because I think its excellent article and sums up many of the frustrations that scientists have with the debate.  

 Here’s an exerpt (referring to Gareth Morgan’s book “Poles Apart“).  You can read the full article here.

But tellingly, before his epiphany, Gareth saw the scientists as “Alarmists” and the other side as “Sceptics”. Completely back to front. Science is inherently a sceptical process and all good scientists are sceptics. But when the web crawls with misinformation on this subject, it’s an easy mistake to make. As Kevin Campbell put it in his email. “Never have so few with vested interests been so wrong and attempted to swindle so many.” He was referring to the scientists.

Pause and ask what motive the scientific community has to gang up and invent a phoney climate crisis. Then compare the motives ExxonMobil, or coal companies, or companies extracting oil from tar sands, might have to deny that burning fossil fuels like there’s no tomorrow could forever change our existence on the planet. Kevin may have motives too – he runs a recruitment company specialising in automotive, heavy diesel and marine industries.

And while we’re talking about climate change, the PM’s chief science advisor, Peter Gluckman has also written an excellent overview of the scientific understanding and potential consequences of climate change.  Read it here.