Science Literature

JBS Haldane, one of the founders of neoDarwinism, when asked what can be learned about God from a study of his creation responded with this aphorism: "that God has an inordinate fondness for beetles". A "preliminary consensus" develops the classification of beetles in terms of 4 sub-orders, 17 superfamilies and 168 families. The 350,000 described species represent about 25% of all named species on planet Earth.

New research has provided a phylogenetic analysis "inferred from three genes and nearly 1900 species" designed to cast light on the evolutionary biodiversity of the Coleoptera. (Source here)

Two popular hypotheses were tested and found wanting.

"Diversification may be driven by feeding strategy, and we tested the hypothesis that feeding on plants (herbivory), and specifically flowering plants (angiosperms), explains the diversity of beetles."

The authors found that:

"Herbivory has played a role in the diversification of some beetle lineages, but the trait per se does not explain why beetles are so diverse."

A second idea is that the Coleoptera speciation rates are particularly rapid. However, this hypothesis was not confirmed either: "Fast diversification rates also do not explain beetle diversity."
More positively, the authors identify three factors explaining why beetles are so numerous:

"Therefore, the extreme diversity of beetles reflects the Jurassic origin of numerous modern lineages, high lineage survival, and the diversification into a wide range of niches, including the utilization of all parts of plants."

Most beetle families have Jurassic roots and they can be described as great survivors. When coupled with their aptitude for occupying a wide variety of ecological niches, beetles display an effective formula for success.
Stephen Jay Gould, in an essay on Haldane's quip, suggests that the key point behind Haldane's words is that "ultimate meaning must reside in the unparalleled diversity of a group that rarely merits our attention." Lessons can be learned by studying the natural world, and if it is not that God is inordinately fond of beetles, what is it? [In passing, materialists ought to stumble over the phrase "ultimate meaning" because in a purely natural world, meaning must be personal and existential. However, Theists should be able to connect with Gould's point without too much difficulty.]

Both the two failed hypotheses have a Darwinian flavour: (a) new environments provided by the evolution of the flowering plants have driven diversification, and (b) fast diversification rates explain the data. These ideas can stimulate very plausible 'just-so stories' - but they are both wrong.

The research conclusions are not particularly Darwinian at all! Diversification and adaptation are not the exclusive province of Darwinian theory. The key findings are: the Jurassic origin of modern lineages, the survival of these lineages, and the aptitude to occupy different ecological niches. If these factors lead us toward "ultimate meaning", then we need models of diversification which can identify the deep roots of modern lineages, better theories of extinction and survival, and better handles on adaptation potential. Thus far, it would appear that the dominance of Darwinism in evolutionary biology has impeded research in these areas.
It is worth noting that the new research complements and strengthens the earlier conclusions of McPeek and Brown (2007):

"Animal taxa show remarkable variability in species richness across phylogenetic groups. Most explanations for this disparity postulate that taxa with more species have phenotypes or ecologies that cause higher diversification rates (i.e., higher speciation rates or lower extinction rates). Here we show that clade longevity, and not diversification rate, has primarily shaped patterns of species richness across major animal clades: more diverse taxa are older and thus have had more time to accumulate species."

A Comprehensive Phylogeny of Beetles Reveals the Evolutionary Origins of a Superradiation
Toby Hunt, Johannes Bergsten, Zuzana Levkanicova, Anna Papadopoulou, Oliver St. John, Ruth Wild, Peter M. Hammond, Dirk Ahrens, Michael Balke, Michael S. Caterino, Jesus Gomez-Zurita, Ignacio Ribera, Timothy G. Barraclough, Milada Bocakova, Ladislav Bocak, and Alfried P. Vogler.
Science 318, 21 December 2007: 1913-1916.

Beetles represent almost one-fourth of all described species, and knowledge about their relationships and evolution adds to our understanding of biodiversity. We performed a comprehensive phylogenetic analysis of Coleoptera inferred from three genes and nearly 1900 species, representing more than 80% of the world's recognized beetle families. We defined basal relationships in the Polyphaga supergroup, which contains over 300,000 species, and established five families as the earliest branching lineages. By dating the phylogeny, we found that the success of beetles is explained neither by exceptional net diversification rates nor by a predominant role of herbivory and the Cretaceous rise of angiosperms. Instead, the pre-Cretaceous origin of more than 100 present-day lineages suggests that beetle species richness is due to high survival of lineages and sustained diversification in a variety of niches.

See also:

Pennisi, E. Meet the Beetles - And Their Crazy Family Tree, ScienceNOW Daily News, 20 December 2007.

McPeek , M.A. and Brown, J.M., Clade Age and Not Diversification Rate Explains Species Richness among Animal Taxa, The American Naturalist, 169 (2007), E97-E106 | DOI: 10.1086/512135

Gould, S.J. A special fondness for beetles, in: Dinosaur in a haystack, Jonathan Cape, London. 1996, 377-387.