Upset Update: Globular Clusters, Atmospheric Methane Tear Up Textbooks
Here are a couple of updates to stories we reported earlier in the category “Everything we thought was wrong.”
- Globular cluster ages: Our 10/05/2003 entry reported that beliefs about globular cluster ages were undergoing a radical revision. You can almost feel the rumblings in a related story on News@Nature; “In a complex Universe, astronomers thought they had at least one simple system to tell them how stars are born. Turns out they were wrong,” reported Jenny Hogan. Other statements say that globulars “aren’t as simple as astronomers used to think,” and that “it’s changing our ideas completely,” and that this will require us to “tear up textbooks.” Moreover, the realization that GCs are not homogeneous collections of ancient stars, but are now seen to contain young blue stars, will have ripple effects. “If you have problems reproducing star formation in globular clusters, you will have problems with a galaxy,” reported one astronomer.
To be sure, a new interpretation is emerging that there were two episodes of star birth in most GCs. Hogan downplays the impact of the revelations, commenting that the new picture “shouldn’t upset long-term calculations of age too much.” To remind us, though, that shouldn’t has an element of wishful thinking in it, she ends: “But, astronomers add, they haven’t yet had time to work out all the implications.”
- Atmospheric methane sources: In a 01/12/2006 entry, we reported the surprising finding that plants contribute a third of the methane budget in Earth’s atmosphere. Nature brought the story up to date in the 08/17/2006 issue (442, 730-731(17 August 2006) | doi:10.1038/442730a). In “The methane mystery,” the magazine said that this finding has “shaken up atmospheric scientists.” The January claim, corroborated by another team in March, “rattled many, because textbooks hold that methane is produced from organic matter decaying in oxygen-free environments, not from living plants,” the news item said. “If true, his finding could account for a substantial fraction of the methane entering the atmosphere – potentially throwing off calculations of how much humans contribute.” Scrutiny of these announcements has not yielded a consensus to confirm or refute the data. Analysis is complicated further by another finding in Brazil that suggests some species can emit 4,000 times more methane than others.
The findings are contentious and may have major ramifications on how atmospheric scientists interpret the human contribution to global warming. The goal now is to collect better data. Nature did not land on a particular side of the debate, but quoted one scientist’s advice, “You need to understand the entire greenhouse budget before you can start thinking about mitigating climate change.”
Both these stories came out of the blue. Both are having major impacts on the way scientists think about subjects over which they used to be confident. Both are overhauling textbook orthodoxies, and both are illustrations of the fact that nothing in science is immune to revision.
Encore: Here’s a story from the University of Bristol, UK, about Neandertals. It begins, “Neandertals were much more like modern humans than had been previously thought, according to a re-examination of finds from one of the most famous palaeolithic sites in Europe….”
Since these are controversial subjects, students should only be taught the standard view. Teachers do not have time to teach the controversy, and it is not the job of public schools to go beyond the prescribed curriculum. Students might be confused by hearing differing views. Despite the credentials of the scientists involved, we can’t be sure they were not politically or religiously motivated. This is how science is done, and if you are going to play the game of science, you must play by the rules. Administrators should prohibit teachers from showing these articles to students under the guise of “supplementary material,” even if they come from the scientific journals. Failure to cease and desist will provide grounds for a lawsuit. (Commentary inspired by Eugenie Scott and the NCSE thought police.)