Male and female contributions to diversity among birdwing butterfly images.

Machine learning (ML) newly enables tests for higher inter-species diversity in visible phenotype (disparity) among males versus females, predictions made from Darwinian sexual selection versus Wallacean natural selection, respectively. Here, we use ML to quantify variation across a sample of > 16,000 dorsal and ventral photographs of the sexually dimorphic birdwing butterflies (Lepidoptera: Papilionidae). Validation of image embedding distances, learnt by a triplet-trained, deep convolutional neural network, shows ML can be used for automated reconstruction of phenotypic evolution achieving measures of phylogenetic congruence to genetic species trees within a range sampled among genetic trees themselves.

Impacts of speciation and extinction measured by an evolutionary decay clock.

The hypothesis that destructive mass extinctions enable creative evolutionary radiations (creative destruction) is central to classic concepts of macroevolution. However, the relative impacts of extinction and radiation on the co-occurrence of species have not been directly quantitatively compared across the Phanerozoic eon. Here we apply machine learning to generate a spatial embedding (multidimensional ordination) of the temporal co-occurrence structure of the Phanerozoic fossil record, covering 1,273,254 occurrences in the Paleobiology Database for 171,231 embedded species.

Deep learning on butterfly phenotypes tests evolution's oldest mathematical model.

Traditional anatomical analyses captured only a fraction of real phenomic information. Here, we apply deep learning to quantify total phenotypic similarity across 2468 butterfly photographs, covering 38 subspecies from the polymorphic mimicry complex of and . Euclidean phenotypic distances, calculated using a deep convolutional triplet network, demonstrate significant convergence between interspecies co-mimics.

Sclerite-bearing annelids from the lower Cambrian of South China.

Cambrian annelids are strikingly diverse and reveal important details of annelid character acquisition. Their contribution, however, to a wider understanding of the evolution of the trochozoans (encompassing the annelids as well as such groups as the brachiopods and molluscs) remains limited. Thus the early annelids had been linked to a variety of cataphract Cambrian metazoans, notably Wiwaxia and the halkieriids, but recent work assigns such fossils to stem-group molluscs.

Nutrient-dependent growth underpinned the Ediacaran transition to large body size.

Macroscale rangeomorph fossils, with characteristic branching fronds, appear (571 Myr ago) after the Gaskiers glaciation (580 Myr ago). However, biological mechanisms of size growth and potential connections to ocean geochemistry were untested. Using micro-computerized tomography and photographic measurements, alongside mathematical and computer models, we demonstrate that growth of rangeomorph branch internodes declined as their relative surface area decreased.

Australian spiny mountain crayfish and their temnocephalan ectosymbionts: an ancient association on the edge of coextinction?

Australian spiny mountain crayfish (Euastacus, Parastacidae) and their ecotosymbiotic temnocephalan flatworms (Temnocephalida, Platyhelminthes) may have co-occurred and interacted through deep time, during a period of major environmental change. Therefore, reconstructing the history of their association is of evolutionary, ecological, and conservation significance. Here, time-calibrated Bayesian phylogenies of Euastacus species and their temnocephalans (Temnohaswellia and Temnosewellia) indicate near-synchronous diversifications from the Cretaceous.

The morphological state space revisited: what do phylogenetic patterns in homoplasy tell us about the number of possible character states?

Biological variety and major evolutionary transitions suggest that the space of possible morphologies may have varied among lineages and through time. However, most models of phylogenetic character evolution assume that the potential state space is finite. Here, I explore what the morphological state space might be like, by analysing trends in homoplasy (repeated derivation of the same character state).

Wing patterning genes and coevolution of Müllerian mimicry in Heliconius butterflies: Support from phylogeography, cophylogeny, and divergence times.

Examples of long-term coevolution are rare among free-living organisms. Müllerian mimicry in Heliconius butterflies had been suggested as a key example of coevolution by early genetic studies. However, research over the last two decades has been dominated by the idea that the best-studied comimics, H.

The size of the character state space affects the occurrence and detection of homoplasy: modelling the probability of incompatibility for unordered phylogenetic characters.

This study models the probability of incompatibility versus compatibility for binary or unordered multistate phylogenetic characters, by treating the allocation of taxa to character states as a classical occupancy problem in probability. It is shown that, under this model, the number of character states has a non-linear effect on the probability of character incompatibility, which is also affected by the number of taxa. Effects on homoplasy from the number of character states are further explored using evolutionary computer simulations.

Fractal branching organizations of Ediacaran rangeomorph fronds reveal a lost Proterozoic body plan.

The branching morphology of Ediacaran rangeomorph fronds has no exact counterpart in other complex macroorganisms. As such, these fossils pose major questions as to growth patterns, functional morphology, modes of feeding, and adaptive optimality. Here, using parametric Lindenmayer systems, a formal model of rangeomorph morphologies reveals a fractal body plan characterized by self-similar, axial, apical, alternate branching.

A simple model explains the dynamics of preferential host switching among mammal RNA viruses.

A growing number of studies support a tendency toward preferential host switching, by parasites and pathogens, over relatively short phylogenetic distances. This suggests that a host switch is more probable if a potential host is closely related to the original host than if it is a more distant relative. However, despite its importance for the health of humans, livestock, and wildlife, the detailed dynamics of preferential host switching have, so far, been little studied.

Phylogenetic codivergence supports coevolution of mimetic Heliconius butterflies.

The unpalatable and warning-patterned butterflies Heliconius erato and Heliconius melpomene provide the best studied example of mutualistic Müllerian mimicry, thought-but rarely demonstrated-to promote coevolution. Some of the strongest available evidence for coevolution comes from phylogenetic codivergence, the parallel divergence of ecologically associated lineages. Early evolutionary reconstructions suggested codivergence between mimetic populations of H.