the importance of using multiple phylogenetic methods when examining complex groups and the utility of software programs that estimate signal conflict within datasets.

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Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. AbstractWe investigate theoretically shear banding in large amplitude oscillatory shear (LAOS) of polymeric and wormlike micellar surfactant fluids. In large amplitude oscillatory shear strain, we observe banding at low frequencies and sufficiently high strain rate amplitudes in fluids for which the underlying stationary constitutive curve of shear stress as a function of shear rate is nonmonotonic. This is the direct (and relatively trivial) analog of quasisteady state banding seen in slow strain rate sweeps along the flow curve. At higher frequencies and sufficiently high strain amplitudes, we report a different but related phenomenon, which we call "elastic" shear banding. This is associated with an overshoot in the elastic (Lissajous-Bowditch) curve of stress as a function of strain and we suggest that it might arise rather widely even in fluids that have a monotonic underlying constitutive curve, and so do not show steady state banding if under a steadily applied shear flow. It is analogous to the elastic banding triggered by stress overshoot in a fast shear startup predicted previously by R. L. Moorcroft and S. M. Fielding [Phys. Rev. Lett. 110(8), 086001 (2013)], but could be more readily observable experimentally in this oscillatory protocol due to its recurrence in each half cycle. In large amplitude oscillatory shear stress, we report shear banding in fluids that shear thin strongly enough to have either a negatively or a weakly positively sloping region in the underlying constitutive curve, noting again that fluids in the latter category do not display steady state banding in a steadily applied flow. This banding is triggered in each half cycle as the stress magnitude transits the region of weak slope in an upward direction such that the fluid effectively yields. It is strongly reminiscent of the transient banding predicted previously in step stress [R. L. Moorcroft and S. M. Fielding, Phys. Rev. Lett. 110(8), 086001 (2013)]. Our numerical calculations are performed in the Rolie-poly model of polymers and wormlike micelles, but we also provide arguments suggesting that our results should apply more widely. Besides banding in the shear strain rate profile, which can be measured by velocimetry, we also predict banding in the shear and normal stress components, measurable by birefringence. As a backdrop to understanding the new results on shear banding in LAOS, we also briefly review earlier work on banding in other time-dependent protocols, focusing in particular on...

6Background: Rubus (Rosaceae) comprises more than 500 species with additional commercially 7 cultivated raspberries and blackberries. The most recent (> 100 years old) global taxonomic 8 treatment of the genus defined 12 subgenera; two subgenera were subsequently described and 9 some species were rearranged. Intra-and interspecific ploidy levels and hybridization make 10 phylogenetic estimation of Rubus challenging. Our objectives were to: estimate the phylogeny 11 of 94 geographically diverse species and 3 cultivars using chloroplast DNA sequences and target 12 capture of approximately 1,000 low copy nuclear genes; estimate divergence times between 13 major Rubus clades; and examine the historical biogeography of species diversification. 14 15 Results: Target capture sequencing identified eight major groups within Rubus. Subgenus 16 Orobatus and Subg. Anoplobatus were monophyletic, while other recognized subgenera were 17 para-or polyphyletic. Multiple hybridization events likely occurred across the phylogeny at 18 subgeneric levels, e.g., Subg. Rubus (blackberries) × Subg. Idaeobatus (raspberries) and Subg. 19 Idaeobatus × Subg. Cylactis (Arctic berries) hybrids. The raspberry heritage within known 20 cultivated blackberry hybrids was confirmed. The most recent common ancestor of the genus 21 Rubus species were examined using limited nuclear and chloroplast loci by Wang et al. (18). 63 Species from Dalibardastrum and Idaeobatus were nested within the paraphyletic 64 Malachobatus. These authors hypothesized that the allopolyploid species in Malachobatus may 65 be derived from crosses between Idaeobatus and Cylactis species (8, 18). Similarly, 66 Dalibardastrum species may be derived from Malachobatus ancestors. Idaeobatus was 67 polyphyletic with members in four clades. Current phylogenies consistently indicate that 68subgeneric labels rarely represent monophyletic groups (17, 18). 69 Hybridization and polyploidization are major evolutionary forces in Rubus. Intraspecific 70 morphological and ploidial variability and the capability of many species to hybridize widely 71 across the genus complicate traditional taxonomic classification (8,(19)(20)(21). Past phylogenetic 72 analyses of the genus were based on nuclear ribosomal DNA internal transcribed spacer (ITS) 73 sequence data and a few other nuclear and chloroplast loci, including GBSSI-2, PEPC, trnL/F, 74 rbcL, rpl20-rps12, and trnG-trnS (17, 18, 22). Relying on a limited number of loci to determine 75 relationships in this genus with prevalent hybridization and polyploidy has resulted in low 76 phylogenetic resolution. Additionally, single gene trees may not represent species trees due to 77 hybridization, incomplete lineage sorting (ILS), and gene duplication (23). 79Two contrasting views of Rubus evolution exist. One view uses a nuclear ribosomal ITS-based 80 genus-wide phylogeny (17) to suggest that the ancestral area for the genus was North America, 81 Eastern Europe (possibly Russia) or Asia (possibly Korea or Japan). In contrast, the treatme...

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