Propaganda Masquerading as News: The Incredible Shrinking Horse

I recently came across a news story which struck me as a good example of how to mislead people, probably for political purposes, without saying anything that was not actually true. The title was "Watch out: Mammals shrink when Earth heats up, study says." The story reported evidence that, at a period when global temperatures were high, a number of ancient mammals became smaller—by fourteen percent in one case, by four percent in another.

There were two things wrong with the story. The first was the repeated use of the term "shrinking." What it was actually describing was evolutionary change, probably over a period of several million years, but the story never said that. It made it sound as though  animals were actually shrinking, and that is how I would expect a casual reader without much scientific background to read it. How else would you interpret "At least twice before in Earth's history, when carbon dioxide levels soared and temperatures spiked, mammals shriveled a bit in size."

At least twice before in Earth's history, when carbon dioxide levels soared and temperatures spiked, mammals shriveled in a bit in size

Read more at: https://phys.org/news/2017-03-mammals-earth.html#jCp

At least twice before in Earth's history, when carbon dioxide levels soared and temperatures spiked, mammals shriveled in a bit in size

Read more at: https://phys.org/news/2017-03-mammals-earth.html#jCp

At least twice before in Earth's history, when carbon dioxide levels soared and temperatures spiked, mammals shriveled in a bit in size

Read more at: https://phys.org/news/2017-03-mammals-earth.html#jCp

The second was the picture that accompanied the story. It shows a modern horse, a Morgan, contrasted with Sifrhippus sandrae. The visual impression is of enormous shrinkage, the modern horse being nearly a hundred times the weight of the ancestral horse. But that is totally irrelevant to the facts being reported, since all of this was happening many millions of years before there were any modern horses.

My conjecture, on which the title of this blog is based, is that the article was designed to mislead, to scare casual readers about the effects of global warming, to make them imagine that it would shrink them by a similar amount. It is possible that I am mistaken, that the author did not care about politics and was merely trying to write a story people would read. Shrinking from the size of a horse to the size of a cat is a much more dramatic story than evolutionary change from the size of a large cat to the size of a medium cat, which is what the story was actually describing.

On either interpretation, I see no plausible way of interpreting the story, in particular the picture, that does not make it a case of deliberately dishonest journalism.