Science Literature

Octopuses are very unlikely to be fossilised. To get anything preserved, exceptional conditions are needed. Palaeontologists have to look in a site identified as Lagerstaette, known for exceptional preservation - often involving soft tissues. One such place is found in rocks from the Middle Cretaceous in Lebanon, known for producing excellent specimens of fossil fish. Over 100 years ago, a fossil octopod named Palaeoctopus was found in these rocks, and additional specimens have not been discovered until now.

"The body of an octopus is composed almost entirely of muscle and skin, and when an octopus dies, it quickly decays and liquefies into a slimy blob. After just a few days there will be nothing left at all. And that assumes that the fresh carcass is not consumed almost immediately by hungry scavengers. The result is that preservation of an octopus as a fossil is about as unlikely as finding a fossil sneeze, and none of the 200-300 species of octopus known today has ever been found in fossilized form. Until now, that is."

The holotype specimen Keuppia levante (Image credit: Dirk Fuchs, Source here)

The new octopuses were worth waiting for. They are remarkable for their condition and have attracted widespread interest. There are three new species of fossil octopus represented by five specimens.

"[These,] astonishingly, preserve the octopuses' eight arms with traces of muscles and those characteristic rows of suckers. Even traces of the ink and internal gills are present in some specimens. 'These are sensational fossils, extraordinarily well preserved' says Dirk Fuchs of the Freie University Berlin, lead author of the report."

The researchers have given the three species names and compared them with living and fossil animals. This is where there was another big surprise. In papers published during the past 15 years, a variety of dates have been proposed for the evolutionary origins of the octopoda. Palaeoctopus was perceived as a stem group animal rather than representative of modern forms. All this has now changed, because one of the three species can be located within the family of extant animals.

"But what surprised the scientists most was how similar the specimens are to modern octopus: "these things are 95 million years old, yet one of the fossils is almost indistinguishable from living species." This provides important evolutionary information. "The more primitive relatives of octopuses had fleshy fins along their bodies. The new fossils are so well preserved that they show, like living octopus, that they didn't have these structures." This pushes back the origins of modern octopus by tens of millions of years, and while this is scientifically significant, perhaps the most remarkable thing about these fossils is that they exist at all."

The first take-home message emerging from the new finds concerns stasis. This theme appears from time to time on this blog and it will continue to do so because stasis is an important characteristic of the fossil record. Darwinians are so fixated on variation that they search avidly for minor changes without embracing the big picture (represented by stasis). For more on this, go here and here.

The second point worth making is that the literature is wedded to the paradigm of evolutionary transformation. There is so strong a focus on tracing evolutionary lineages that other explanatory frameworks are not even considered. All variants tend to be given an evolutionary interpretation, and the grand claim is made: these new finds help us understand the way these animals evolved. In the case of octopods, there is so little data that any claims like this should be treated with suspicion. We do not know what environmental factors could be influencing the way animals speciated and we cannot say with any confidence whether there was an evolutionary trajectory or a bush-like diversification. The discovery of a member of the Recent family Octopodidae at least puts some constraints on evolutionary speculations.

New Octopods (Cephalopoda: Coleoidea) From The Late Cretaceous (Upper Cenomanian) Of Hakel And Hadjoula, Lebanon
Dirk Fuchs, Giacomo Bracchi and Robert Weis
Palaeontology, 2009, 52(1), 65-81 | doi 10.1111/j.1475-4983.2008.00828.x

Abstract: Three previously unknown octopods are described from Upper Cenomanian limestones of the Haqel and Hadjoula localities (Lebanon). Keuppia levante gen. nov., sp. nov., Keuppia hyperbolaris gen. nov,. sp. nov. and Styletoctopus annae gen. nov, . sp. nov. are regarded as the earliest representatives of the Octopoda (= Incirrata). [. . .]. Based on a pair of widely separated stylets, which closely resemble the rods of modern octopods, Styletoctopus annae gen. nov., sp. nov. is assigned to the Recent family Octopodidae. [. . .] The surprising existence of a stylet-like gladius vestige in Styletoctopus annae sp. nov. suggests that the octopod clade branched off much earlier than previously believed. Octopod apomorphies such as the development of stylets, loss of fins and cirri must have been occurred before the Cenomanian.

See also:

Dell'Amore, C. Rare Octopus Fossil Found, National Geographic News, March 19, 2009

Cretaceous octopus with ink and suckers - the world's least likely fossils? EurekAlert, 17 March 2009