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Darwin’s “Abominable Mystery”: Jurassic Flowering Plants After All?

Photo: Tropidogyne pentaptera, a mid Cretaceous flower from Burmese amber, by Oregon State University (license CC BY-SA 2.0), via Flickr.

I have been discussing Darwin’s “abominable mystery” — the abrupt origin of flowering plants (see here and here). I noted that two new studies claim progress in solving this problem. This year a new article by Silvestro et al. (2021), “Fossil data support a pre-Cretaceous origin of flowering plants,” was published in the prestigious journal Nature Ecology & Evolution. It claimed that the fossil record proves that flowering plants already existed in the Jurassic period or even earlier. Sounds like they finally discovered the elusive Jurassic ancestors of flowering plants!? Indeed, the popular press headlined, “Flowering plants may be 100 million years older than we thought” (Sawal 2021) and “Study: First Flowering Plants Appeared in Jurassic Period or Even Earlier” (SciNews 2021). The official press release announced, “New study unravels Darwin’s ‘abominable mystery’ surrounding origin of flowering plants” (University of Bristol 2021).

Did It Really?

In spite of the hype, this study is highly problematic. You do not have to take my word for that, because even some mainstream evolutionists agree, such as Patrick Herendeen from the Chicago Botanic Garden in a skeptical comment quoted in New Scientist (Sawal 2021). Herendeen is skeptical of the findings “because missing fossil data could affect the results.” Missing fossil data? Sounds suspicious, so, what did the new study really discover to justify the grand claims? Silvestro et al. (2021) looked at the statistical distribution of the oldest fossil representatives for modern angiosperm families only, which are exclusively Tertiary and Cretaceous in age. Similar to many molecular clock studies (Bell et al. 20052010Smith et al. 2010), which totally contradict the fossil record (Coiro et al. 2019), and similar to some other studies (Li et al. 2019), they then extrapolated the history of these groups back into the Jurassic with a so-called ghost lineage, even though there are no Jurassic fossils. You heard that right: They did not find any Jurassic fossils of flowering plants, not a single one! To explain away the conflicting evidence, the authors had to invoke a completely ad hoc hypothesis that was pondered by Charles Darwin in his 1879 letter to Hooker, namely that angiosperms evolved slowly as a rare and small group in a remote and hidden region (Barba-Montoya et al. 2018Sgorbati et al. 2018), which therefore evaded the fossil record. But if we consider the numerous fossil localities around the globe with thousands of Jurassic plant fossils, but no angiosperms among them, this cheap cop-out is simply not plausible and not warranted by any positive evidence. It is a desperate attempt to shield a cherished theory against empirical falsification, and that is definitely not how good science should be done.

An Even More Fundamental Problem

But there is an even more fundamental problem with this study. The authors’ claim is based on two question-begging assumptions: common descent (which I would even grant), and a gradual, slow neo-Darwinian mechanism of evolution. Only based on these two assumptions can they postulate and extrapolate a ghost lineage back into the Jurassic. The actual fossil record clearly contradicts their prediction, and thus suggests that at least one of their two hidden assumptions is wrong. In my view this is clearly the neo-Darwinian unguided process, which is also undermined by many other lines of evidence, such as the waiting time problem or the combinatorial search space problem. This is why neo-Darwinism is indeed increasingly questioned and rejected by leading theoretical biologists (Nelson & Klinghoffer 2016), and not just by us Darwin critics and intelligent design proponents.

The study by Silvestro et al. (2021) does not unravel but rather confirms Darwin’s “abominable mystery,” because it shows that Darwin’s intuition was correct: if the evolution of angiosperms before the Cretaceous was at the same rate/mode/tempo as the evolution of angiosperms after the Cretaceous, then there should be Jurassic angiosperm fossils. Given that Jurassic angiosperm fossils have not been found, this study provides new confirmation of the abominable mystery, not its solution. That is not just my humble opinion, but has also been expressed in two tweets by Richard Buggs (see Twitter, here and here).

Next, “Darwin’s ‘Abominable Mystery’: Mesozoic Cupules Come to the Rescue?”