The 'Map of Life': Convergent evolution for all

Cambridge University press release; also to be published in Issue 14 of Research Horizons magazine in April.  © 2010 News, University of Cambridge.

http://www.admin.cam.ac.uk/news/dp/2011030302

 Thorny devil (Moloch horridus) at Great Central Road (WA) 2006, Bäras, GNU FDL

A new website that explains why humans have the same type of eye as an octopus, and how animals separated by millions of years have evolved in the same way, has been launched by a team of scientists at Cambridge University.

The Map of Life (www.mapoflife.org) highlights hundreds of examples of 'evolutionary convergence' such as Australia's thorny devil lizard (pictured) and North America's desert horned lizard.

Despite being separated by 150 million years of evolution, both lizards have evolved the same way of collecting drinking water through their skin. The new website also explains why the fiery colours of autumn leaves that adorn hundreds of different tree species are examples of convergent evolution, as well as exploring the similarities between ants that farm and sea cows that graze.

The Map of Life project is coordinated by Professor of Evolutionary Palaeobiology Simon Conway Morris in the Department of Earth Sciences to provide an accessible website for the public, as well as for students and academics.

Dr Chloe Cyrus-Kent, a member of the team behind the Map of Life, will be at this month's Cambridge Science Festival (www.cam.ac.uk/sciencefestival), the UK's largest free science festival, providing a chance to explore who's related to whom through convergent evolution, whether it be among gliding animals, desert plants or burrowing creatures.

She said: "Convergent evolution occurs when unrelated organisms acquire similar adaptations to life in similar environments but from very different starting points. In this way, creatures with common solutions to challenges in their unique habitats can occupy very distant branches of the tree of life. Perhaps one of the most startling example is the similarity between our eyes and those of the octopus."

Professor Conway Morris, Dr Cyrus-Kent and Dr Verena Dietrich-Bischoff have spent several years assembling hundreds of examples of convergence and writing the topic-based content of the website, the first of its kind.

Sponsored by the John Templeton Foundation, the Map of Life shows that the living world not only evolves, changing over time as successive generations inherit modified information from their predecessors, but often do so along strikingly similar pathways despite being unrelated to each other.

"With Darwin we saw our world through new eyes," said Conway Morris, "but perhaps with convergence we see new landscapes in evolutionary biology, reflecting a deeper order within living systems."

Mathematicians.

Fantastic quote from Thursday's seminar on fluid dynamics:

"Then you get an infinitely long, circular mountain."

Hmm.  I'd like to see the topo map for that one.

The Lagginhorn:  It's not circular, but it seemed infinitely long...

(Photo R Berkowitz, July 2009)

New cell death mechanism has implications for breast cancer treatments

Press release published by Cambridge University, 22 Feb 2011, © 2010 News, University of Cambridge.  http://www.admin.cam.ac.uk/news/dp/2011022402


A novel mechanism of cell death that occurs in mammalian organisms has been revealed by researchers at the University of Cambridge.

Section of a mammary gland in which cells have been shed from the lining of the milk-producing structures and are undergoing cell death. 

(credit: Peter Kreuzaler, Cambridge University Department of Pathology)

Billions of damaged or superfluous cells die in our bodies every day. It is thought that most cell death occurs by a process called apoptosis, in which biochemical events lead to cell changes and death.

However, during the course of Peter Kreuzaler's PhD research at the Department of Pathology, the Cambridge team have shown that cells in the breast die following lactation by a process that involves lysosomes - organelles which digest and recycle cellular components.

As the mammary gland regresses, enzymes called cathepsins leak out of the lysosomes into the cell and induce cell death. This is the first time that this type of cell death has been shown to occur in a healthy mammal: the original work was done in vivo in mice. Additionally, the protein Stat3, which is present in high levels in cancers that have poor prognosis, plays a significant role in lysosomal-mediated programmed cell death as it induces high levels of cathepsins while suppressing cathepsin inhibitors.

Describing how the work was done, Professor Christine Watson of the Department of Pathology said: "We found a gene that was hugely down-regulated by Stat3."This gene inhibits lysosomal enzymes, so [we] started looking at these."
The team's findings will cause scientists to think differently about how cells die.

Kreuzaler added, "Our work is the first to show that a lysosomal pathway of cell death occurs in a normal situation in the body. Current cancer research focuses on understanding how cancers evade cell death. The discovery of a novel pathway of cell death is likely to explain a yet unexplained tumour resistance to cell death, while giving researchers new prospective therapeutic targets."

According to Watson, the most exciting thing about this work is that the team have identified a new form of cell death that has major implications for cell death research and for treating people with breast cancer.

The research, recently published in the journal Nature Cell Biology, was funded by studentships from the Department of Pathology and the Breast Cancer Campaign, as well as the Biotechnology and Biological Sciences Research Council and the Medical Research Council.

The next steps will be to take advantage of this as a death pathway in breast cancer in particular, and to see how this pathway actually operates and is controlled. She plans to investigate whether the same process works to kill cancer cells in culture. While a treatment based on this new cell death mechanism is far in the future, Watson thinks that a therapy based on lysosomal-mediated cell death could target very aggressive cancers.

The ‘bear’ necessities of hibernation

Published on BlueSci website, 24 Feb 2011, copyright Cambridge University.
http://www.bluesci.org/?p=2124

 

“I wish I could hibernate like a bear this winter!” This sentiment is often expressed by Cambridge University students as they slog through the darkest moments of their degrees. But they might want to reassess what “hibernate like a bear” really means.

 

Black bears display unusual patterns of metabolic and thermal regulation during hibernation as well as when they emerge in the spring, causing some biologists to question whether or not they really hibernate. Hibernation is a powerful way to reduce energy costs; in small mammals it involves lowered body temperatures and metabolic activity interrupted by periods of arousal and increased temperatures. However, a study based at the Institute of Arctic Biology at the University of Alaska found that hibernating black bears lack the periods of arousal. Furthermore the study, which made continuous measurements of oxygen consumption, body temperature and heart, muscle, and brain activities, showed that the bears maintained surprisingly high body temperatures during hibernation yet suppressed their metabolism to 25% of basal rates¹.

Upon emerging from hibernation, black bears maintain a reduced metabolic rate for up to three weeks. This suggests that metabolic suppression during hibernation is independent of lowered body temperature, and basal metabolic rate is not a constant but rather is physiologically controlled. 

Further research may show that a torpid state via active metabolic inhibition is the primary means by which mammals can conserve energy.


1. Heldmaier, G. (2011). Life on Low Flame in Hibernation. Science, 331(6019), 866 -867. doi:10.1126/science.1203192 [↩]

Clegg promises libel law reform

My first story on the ABSW website on Clegg's support for British libel law reform!
Published here:  http://www.absw.org.uk/news-events/news/730-clegg-promises-libel-law-reform
© 2009 Association of British Science Writers

This spring the Coalition Government will launch its draft Defamation Bill to reform libel laws that "are having a chilling effect on scientific debate and investigative journalism," according to deputy prime minister and Liberal Democrat leader Nick Clegg in his speech on civil liberties on 7 January.
This reform will make Britain the first country to ask its legislative body to set out its libel laws and provide greater clarity. Clegg is committed to relaxing Britain's libel laws so that academics and journalists are not "bullied into silence" for fear of being sued. Lord Tom McNally, Liberal Democrat minister in the justice department, is preparing the bill.

The draft will be published in late March and the final version will be published this summer according to an interview with Sile Lane, campaigns manager for Sense About Science, a charitable trust and part of the Libel Reform Campaign. Final legislation could be enacted by 2012.

The bill will include restrictions on corporate and public bodies and will bring the law up to date. It will also simplify and strengthen existing defences and restrict libel tourism in which plaintiffs file libel suits in jurisdictions likely to give a more favourable result. A new statutory defence will be provided for journalists and scientists who speak out on important issues.

In his speech, Clegg said that "beyond providing greater access to information, [the government needs] to make sure that, where people discover injustice and bad practice, they can speak out against it too".

Sense About Science conducted a survey which showed that "a third of editors of academic journals said the[y] had been threatened with libel actions," Lane told ABSW. Editors have "asked for changes in how papers were written, to protect themselves from libel actions".

Recent cases bring to light the need for reform. Science writer Simon Singh experienced a lengthy court battle with the British Chiropractic Association over an accusation of libel for an article in which he questioned certain chiropractic practices. Cardiologist Peter Wilmshurst fought a libel case brought against him by an American company after he criticised their research at a medical conference.

"Nobody wants to get rid of libel, but at the moment the law is unfair and entirely hostile to free speech and overly friendly to rich bullies trying to silence criticism," Singh told the ABSW. “The campaign for libel reform is about striking a fairer balance between claimants and defendants.”

John Kampfner, chief executive of the Index on Censorship which is part of the Libel Reform Campaign, wrote in The Independent: "We aim to repair a body of law that has seen countless individuals and voluntary organisations either sued in court or forced into apologising for and retracting comments, articles, and books, even though they have done nothing wrong."

"People who might oppose radical changes [to libel law] would be big libel claimant lawyer firms," said Lane. Libel law is complex and claimant lawyers may argue that it is too specialised to be handled anywhere besides the high courts. This can lead to expensive cases involving long exchanges before trial, according to Tracey Brown, managing director of Sense About Science.

"Why do we assume libel should be a matter for high court?" asked Brown in her post for The Guardian’s OrganGrinder blog. She noted that according to human rights law, all EU member states must provide a remedy for damage to reputation. However, Brown added in her blog, this need not be done "through an arcane, chillingly expensive law in a higher court ... the defamation bill, if it delivers the fundamental reform so many are asking for, will make possible new ways of handling defamation."

Writers, publishers, NGOs, human rights lawyers, clinicians, academics and performers have emphasised different problems with the English libel law. But they all agree that rebalancing libel laws to protect free expression will require fundamental changes to the law and that libel laws are a matter for Parliament as well as the courts.

“Libel law was devised to avoid dragging someone's good name [through] the mud,” Tom Sheldon of the Science Media Centre, an organisation that promotes the views of the scientific community to the national media, told ABSW.  "We want to see a law that allows scientists to comment on what evidence tells them, without being concerned whether that will offend shareholders, company directors, etc."

Clegg's said in his speech that "our aim is to turn English libel laws from an international laughing stock to an international blueprint."

I don't think we're in Kansas anymore.

I've been living in the UK long enough that it feels like home.  Perhaps more so than America.  Hell, I've even been accused of having lost a bit of my accent (what accent?  Washingtonians don't have an accent, we're perfect just as we are!).  But there are just a few things that keep reminding me that this place is foreign.

1.  My supervisor's pronunciation of "capillary."  It's CAPillary!

2.  Using "u" in honour and colour and an "o" in foetus.  I do this now too, but with a wee(!) bit of hesitation.

3.  British musical note values:  quarter notes are crotchets, eighths are quavers, half notes are minims.  I can do this fluently now, but I still think about it.

4.  Thinking that I can go to London at the drop of a hat.  I told my Dad that I wanted to get away from work for the day and just do something different that doesn't involve being cold and wet and in pain (my normal choice of weekend activities), so I might head down and check out some museums and snoop for story ideas to pitch to journals.  And he pointed out how fabulous it is, from the point of view of our little town in eastern WA, to be able to do that so casually.  He's very right.

And it's still a little exciting to be able to drive to France in a day.

A Plume of Gas and Public Interest

Deepwater Horizon oil spill:  24 May 2010, NASA image (photo from Wikimedia Commons, NASA Goddard Space Flight Center)

The Deepwater Horizon blowout left an oily taste in the mouths of a lot of environmental groups.  But the taste is worse when you add in the extent of hydrocarbon gas release.

A University of Georgia-led study co-authored by Florida State University oceanographer Ian MacDonald found that up to 500,000 tons of gaseous hydrocarbons were emitted into the deep ocean.  This generated concentrations of 75,000 times the norm and could result in zones of oxygen depletion as microbes degrade the gaseous hydrocarbons.

The amount of gas released by the blowout is critical for determining potential impacts on deep oceanic systems.  The depth of the blowout (nearly 1 mile) is significant because the hydrocarbon gases become trapped in the water column.

Then, microbes consume the gases which leads to low-oxygen waters.  And the timescale for replenishing oxygen is many decades.

It's difficult to separate oxygen depletion due to gas from that due to liquid hydrocarbons.  Therefore, documenting the total mass of discharged hydrocarbons is important for understanding the long-term implications for the Gulf's microbial communities and food chain.

The team calculated the gas discharge to be equivalent to 1.6 to 3.1 million barrels of oil.  This figure encompasses a lot of uncertainty, but even the lowest is a significant increase in total discharge.

Where exactly has all of the gas gone?  Also difficult to say, as the shifting small-scale currents in the Gulf have probably dissipated the plumes and the associated low oxygen zones.  And it will take a long time for the microbes to consume all the gases released:  they need other nutrients which are in scarce supply, and once these nutrients are depleted, the microbes won't be able to grow.

The opportunities for multi-disciplinary modeling of fluid dynamics and microbiology and economic and social effects are endless.

It's been nearly a year since the blowout.  The plume of upset and urgency seems to have diffused quite a bit since then; with stories like this cropping up reasonably frequently but without nearly the publicity that they would have had nearer to the event.  It might be interesting to model public interest in a particular disastrous event (I'd hate to call it a "natural disaster") as a source plume.  Now that's a PhD thesis waiting to happen.