There are no fossil ancestors of insects

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Contents

Claim

Insect fossils appear in abundance, but the record of insect origins is completely blank.

Source

Responses

  1. This claim is only correct in the extreme technical sense: we have not found (or more accurately, confirmed) any fossils of monocondylic insects (those with a primitive mandible connections, such as bristletails) that predate the Devonian, from where we have at least one dicondylic insect (with modern mandible connections) (but see point #2). This technical detail in no way detracts from the theory of evolution. It’s not as if paleontologists found a preponderance of mixed derived and basal insects in the same ancient strata, a find that would certainly shake how we think insects appeared. On the other hand, we do have the extant bristetails, and DNA and morphological evidence pointing to their split from the early insects before the more modern jaw connection appeared. This particular evolutionary relationship is a hypothesis, which could be confirmed by the discovery of a monocondylic fossil predating the Devonian, or falsified by the discovery of enough evidence contradicting the current thought of how the mono/dico relate to each other.
  2. What do you call an early insect? There are hundreds of “early insect�? fossils in museum drawers across the world, and many more are dug up every year. When paleontologists complain about not having an early fossil, they mean an extremely basal specimen (very close to the split of insects from other arthropods). The ‘problem’ is that as soon as they discover an older fossil, they immediately start searching for an even older one. A paleontologist’s job is never done, but this doesn’t mean we don’t have very old fossil insects (although see point #1 for a strict answer).
  3. Even if this claim were true, the theory of evolution is not invalidated by lack of a particular fossil (negative evidence), but is instead demonstrated by overwhelming positive evidence, e.g. thousands of fossils neatly ordered over hundreds of deposits across the world. Besides, this a claim that’s impossible to satisfy. If you show a new transitional fossil between Fossil A and Z (let’s call the new fossil ‘G’) Creationists ask for fossil C and P. When C and P are dug up, then they ask for B, F, Q and W, and so on. That is, until you can show a fossil from an organism of every population that ever existed on this planet, you can always ask for more intermediate forms. This counter-argument, on the other hand, does not make evolution unfalsifiable. Many types of fossil evidence could falsify that insects have evolved: the sudden appearance across sites of primitive and highly derived forms in the same stratum, a predominance of ‘de novo’ structures with no resemblance to previous forms, and a mixture of all sorts of insects across strata, regardless of geological age. None of this has been found.
  4. Until 2004, fossil insect experts believed the two oldest insects were two very old wingless insects from the Devonian period of North America. In Feb 2004, Engel and Grimaldi (from the American Musuem and the Nat. Hist. Museum of the U of Kansas) published a report that they had found an even earlier insect, Rhyniognatha hirsti. The fact that this fossil has some characters shared with winged insects does not mean that it is recent, but rather that winged insects appeared earlier than previously thought. This work also shows that insects originated in the Silurian period and were members of some of the earliest terrestrial faunas.
  5. There are literarily hundreds of fossilized insect deposits throughout all continents, and including dates from the Devonian to the Holocene. When Engel and Grimaldi (two fossil insect experts) point out that 'only a few fossils provide insight into the earliest stages of insect evolution', they refer to the very early stages of the first insects, not the whole insect fossil record, which they say, is richer than for many vertebrate taxa. They even go on to write a whole 700+ page book on insect evolution base primarily on fossil data!
  6. This is problematic for creationism because there is a pattern of increasing abundance of individual fossils. As the fossils occur in terrestrial deposits, and often amongst plant material, it is difficult to see why they should be rare early on in the record and progressively more common further up if they were all the remains of animals buried in Noah's Flood.
  7. A lack of early forms is expected from an evolutionary perspective, but not so from a creationist one. If the first insects evolved, you’d expect a small initial population, leaving few, if any fossils. If God had created insects in one big zap, you’d expect all of them to show up in the fossil record right from the very early times. While we don’t have fossil specimens from the very early stages of insects, we do have a plethora of transitional forms accounting for all the extant taxonomic orders. It is a problem of creationists to explain this.

References

  1. Engel, M. S. and Grimaldi, D. A., 2004. New light shed on the oldest insect. Nature 427: 627-630
  2. Gaunt, M.W. and Miles, M.A., 2002. An insect molecular clock dates the origin of the insects and accords with palaeontological and biogeographic landmarks. Mol Biol Evol. 19(5): 748-761.
  3. Labandeira, Conrad C., Bret S. Beall, and Francis M. Hueber, 1988. Early insect diversification: Evidence from a Lower Devonian bristletail from Quebec. Science 242: 913-916.
  4. Whalley, Paul and E.A. Jarzembowski, 1981. A new assessment of Rhyniella, the earliest known insect, from the Devonian of Rhynie, Scotland. Nature 291: 317.

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