Press Release Science: ‘Dissolving Starfish’ – Debunked

By Kip Hansen – Re-Blogged From

press-release_420Every author I have ever queried about a quote attributed to them in a University Science Press Release has told me the same thing.

“That’s not exactly what I said, and not what I really meant,” they tell me.  I can feel the shy grins on their faces as I read their replies.  They are usually rather perplexed as to how the press release sent out to the media by their own academic institution came to contain such a questionable quote but almost always seem to shrug it off with good sense of humor. After all, what can they do?




This does not come as any surprise to those of us who follow science news — there are whole internet enterprises dedicated to nothing but gently re-writing University press releases on the science and medical research done on their campuses and promoting the latest journal articles published by their professors and students.  In 2014, in the BMJ (formerly the British Medical Journal), Ben Goldacre wrote an editorial “Preventing bad reporting on health research” in which he insisted that “Academics should be made accountable for exaggerations in press releases about their own work”.  The editorial accompanied a study (Sumner et al. 2014) that “found that much of the exaggeration in mainstream media coverage of health research  — statements that went beyond findings in the academic paper — was already present in the press release sent out to journalists by the academic institution itself”.  I’m not sure I agree fully with Goldacre that academics should be “made accountable” for the exaggerations of the folks in the University Media or PR department — but academics and corresponding authors  should insist on pre-publication approval of any and all statements issued by the media office about their research.

We often see here at WUWT short posts about some Press Release regarding a new journal paper aghast at what some scientist has said — well, “said” according to the press release.  We’ve had a recent example here:

Study: CO2 causes Starfish to Dissolve — a typical skeptical look at a university press release (from Heriot-Watt University in Edinburgh, Scotland) titled “Carbon dioxide ‘pulses’ threaten Scotland’s coralline algal reefs”.

In this press release, Dr. Heidi Burdett is quoted as saying;

“We found that there was a rapid, community-level shift to net dissolution, meaning that within that community, the skeletons of calcifying organisms like star fish and coralline algae were dissolving.” [emphasis added — kh ]

I can imagine the thoughts running through the minds of the men-and-women-on-the-street — “Oh, those poor starfish, writhing in pain as their skeletons dissolve! The horror of it.”

Our home team author, Eric Worral, quotes the abstract of “Community-level sensitivity of a calcifying ecosystem to acute in situ CO2 enrichment in his post. The abstract says nothing about poor dissolving starfish.  We would have been treated to a link to the full-study but unfortunately it was not only behind a fire-wall but also accidentally hidden by a broken link.

Bad and Poor Science Journalism is a particular interest of mine and this (the University Press Release, not Eric’s post) looked like a good example.  Being denied a look at the full study by fire-walling and my usual work-around stymied by a bad DOI link, I took my ‘when-all-else-fails’ approach and emailed Dr. Burdett with a request for pdf copies of the study and its supplemental information, which she promptly sent along with a pleasant note.

We need to understand what the study is about and what its findings are before we revisit the press release.

 What’s the study about?

Dr. Burdett’s study is about “acute in situ CO2 enrichment” and its effects on the salt water chemistry in a “calcifying ecosystem”.    That’s a mouthful.  The field of study is known as “Ocean Acidification” [OA] — the fact that as CO2 concentrations increase in the atmosphere, sea water absorbs some of this CO2 at the surface and that absorption brings about this chemical reaction:


Sea water carbonate bio-chemistry is extremely complicated.  So complicated that even scientists originally studying OA tended to get it wrong — so a field-wide effort was made to set this situation right (after a get deal of effort and money were mostly wasted) part of which I wrote about here at WUWT in “Ocean Acidification: Trying to Get the Science Right” and its follow-up “Dr. Christopher Cornwall Responds to “Ocean Acidification: Trying to Get the Science Right”.  Magnificent detail is available in the 2011 250-page report “Guide to best practices for ocean acidification research and data reporting” published by the now-defunct EPOCA (European Project on OCean Acidification). Chapters 1 and 2 cover the basic chemistry and can be downloaded individually at the link above.

[UPDATE & CORRECTION 12 Mar 2018, 1100 hrs ET:  Reader Kristi Silber correctly reports that the EPOCA web site no longer delivers the “Guide to Best Practices….” pdfs.  Those interested in the Guide can download the entire report at this link:

Exactly why the <b>International Atomic Energy Agency</b>web site  has a Climate Change section and hosts this document is a mystery to me (but I appreciate it!) — kh ]

If we over-simplify quite a bit, we can say that as CO2 mixes with sea water it tends to consume available carbonate ions forming bicarbonate ions and it is this aspect that interferes with  (impedes) biological calcification.  The mixed CO2 also lowers pH (the ‘acidification’ in OA).  This represents pretty well understood sea water carbonate biological chemistry.  The not-so-simple chemistry is complicated by the fact that some corals and other organisms have been found to manipulate the pH of the sea water in direct contact with themselves in a protective manner.

In this experiment, Dr. Burdett’s team studies CO2-enriched sea water and its effect on a “calcifying ecosystem” which looks something like this:


The pinkish nodules and little nubs are coralline algae and the pointy-wavy things are brittle stars (a relative of “starfish”) which “have five long, slender, flexible, whip-like arms…supported by an internal skeleton of calcium carbonate plates …”  [Brittle stars come in all sizes and colors]. Coralline algae are red algae … characterized by a thallus that is hard because of calcareous [that is, composed of calcium carbonate] deposits contained within the cell walls.   Obviously, calcium carbonate, and thus carbonate chemistry, is a major aspect of this ecosystem — a “calcifying ecosystem”.

The experiment is carried out in situ — meaning “in place”.  Right out there in about 6 meters (18 feet) of water in Loch Sween, Scotland, UK.  [Loch means “lake”, but of course this is really a “sea loch”, a seaside bay.]   Tubes with a diameter of 38 cm (15 inches) and a height of about 25 cm (making up a volume of 28 liters or 7.3 gallons)  were pushed down into the seabed enclosing some of that ecosystem pictured above and mounted with a lid with tubes and mixing paddles. Enclosed water was pumped to the surface where a mixing chamber bubbled in pure CO2 sufficient to lower pH by 0.2 pH units below ambient water pH, and the CO2-enriched water was returned to the experimental chamber on the sea floor.  4 such units were used.

Now comes the acute part.  Acute means “of abrupt onset, of short duration, and is a measure of the time scale of a condition.”  In this experiment, it means that after 15 hours, the researchers suddenly raised the CO2 concentration in the water (sufficient to lower pH by 0.2 units), kept it raised for 28 hours, and then shifted back to ambient conditions for 37 more hours. Water samples were taken at various times.   All this underwater work was done with the aid of scuba gear.

So — what did they find when they did all this?  They found that if they more than doubled the dissolved CO2 [p CO2 (µatm)  from 821.6±343.4  to 1747.7±1403.33],  then bicarbonate levels increased, along with dissolved inorganic carbon.

The conclusion drawn from these measurements:


“Under ambient CO2 conditions, the coralline algal community consistently exhibited a net calcification. During CO2 enrichment, a significant shift towards net dissolution was observed.”

[Note: there were several other conclusions about other technical points of sea water carbonate chemistry.]

A shift towards “net dissolution” — and what is that exactly when it puts on its best face to go out in the morning?  I asked Dr. Burdett by email and received this reply:


“…what is meant by ‘net dissolution’ – this means that, at that point in the experiment, there was more dissolution of calcium carbonate than there was production. The loss may have come from live, calcified organisms such as coralline algae or starfish, dead carbonate skeletal remains or carbonate-rich non-biogenic sediment. Since we adopted a community-level approach, our measurements only give an indication of what is happening to the ecosystem as a whole – it is not possible to [identify] the individual components that are contributing to any differences we saw.”

Or, in other words, in the complex and complicated world of sea water carbonate chemistry, the sudden doubling of CO2 dissolved/mixed in the sea water in these chambers altered either (or both) the inorganic or the organic elements of carbonate chemistry inside the chambers — resulting in higher levels of both dissolved inorganic carbon and HCO3(bicarbonate) — indicators that “there was more dissolution of calcium carbonate than there was production.”

This was an expected and interesting result.


What the Press release said: “the skeletons of calcifying organisms like star fish and coralline algae were dissolving.”

What the paper said: “a significant shift towards net dissolution was observed.”

What Dr. Burdett meant: “there was more dissolution of calcium carbonate than there was production. The loss may have come from live, calcified organisms such as coralline algae or starfish, dead carbonate skeletal remains or carbonate-rich non-biogenic sediment.”

There were no starfish writhing in agony as their skeletons dissolved, as might have been inferred by the general public reading the Press Release alone.

LESSON LEARNED:  Never judge a study or its author by the contents of a University media release and never assume that the quotation marks around a statement from a study’s author signify words actually uttered or the meaning intended by the author.

# # # # #

End Note:

















There’s another recent example: the paper highlighted in Science last week regarding coral sediments dissolving was reproduced in many media outlets stating “coral reefs will dissolve”, which is completely different to the findings of the paper.  The Science News article was “Ocean acidification is causing coral reefs to dissolve” commits the same offense as the media release in the main essay above but in reference to “Coral reefs will transition to net dissolving before end of century”.   Even the title of the paper itself is very misleading – the study is about dissolving calcium carbonate (CaCO3) sands, not the reefs themselves, and deals with Aragonite Saturation State, one of the aspects of the complicated subject of sea water carbonate chemistry.





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