Evolution of leaf-cutter behavior in bees (Hymenoptera: Megachilidae) as inferred from total-evidence tip-dating analyses

AbstractA unique feature among bees is the ability of some species ofMegachile s.l. to cut and process fresh leaves for nest construction. The presence of razors between the female mandibular teeth (interdental laminae) to facilitate leaf-cutting (LC) is a morphological novelty that might have triggered a subsequent diversification in this group. However, we have a limited understanding of the evolutionary origins of this behavior and associated structures. Herein, we use total-evidence tip-dating analyses to infer the origin of LC bees and patterns of variation of interdental laminae. Our datasets included five nuclear genes, representatives of all fossil taxa, 80% of the extant generic-level diversity of Megachilidae, and the full range of generic and subgeneric diversity of Megachilini. Our analyses support the notion of a recent origin of LC bees (15–25 Ma), casting doubts on Eocene trace fossils attributed to these bees. We demonstrate that interdental laminae developed asynchronicaly from two different structures in the mandible (teeth or fimbrial ridge), and differ in their phenotypic plasticity. Based on the phylogenetic results, we propose robust classificatory solutions to long-standing challenges in the systematics of Megachilidae. We discuss the implications of our findings as a foundational framework to develop novel evolutionary, ecological, and functional hypotheses on this behavior.

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Morphological phylogeny of Megachilini and the evolution of leaf-cutter behavior in bees (Hymenoptera: Megachilidae)

Journal of Melittology ◽

10.17161/jom.v0i85.11541 ◽

2019 ◽

pp. 1-123 ◽

Cited By ~ 6

Author(s):

Victor H. Gonzalez ◽

Grey T Gustafson ◽

Michael S Engel

Keyword(s):

New Genus ◽

Cladistic Analysis ◽

Sister Group ◽

Morphological Characters ◽

Total Evidence ◽

New Combination ◽

Leaf Cutting ◽

New Tribe ◽

Mandibular Teeth

A unique feature among bees is the ability of some species of Megachile Latreille s.l. to cut and process fresh leaves for nest construction. The presence of a razor between the female mandibular teeth (interdental laminae) to facilitate leaf-cutting (LC) is a morphological novelty that might have triggered a subsequent diversification in this group. However, we have a limited understanding of the phylogeny of this group despite the large number of described species and the origins and patterns of variations of this mandibular structure are unknown. Herein, using a cladistic analysis of adult external morphological characters, we explored the relationships of all genera of Megachilini and the more than 50 subgenera of Megachile s.l. We coded 272 characters for 8 outgroups and 114 ingroup species. Depending on the weighting scheme (equal or implied weighting), our parsimony analyses suggested the monophyly of Megachile s.l. and that either Noteriades Cockerell or the clade Coelioxys Latreille + Radoszkowskiana Popov is the extant sister group of all other Megachilini. In addition, we conducted Bayesian total-evidence tip-dating analyses to examine other possible hypotheses of relationships and patterns of variation of the interdental lamina. Our analyses suggest that interdental laminae developed asynchronicaly from two different structures in the mandible, and differ in their phenotypic plasticity. Character correlation tests using phylogenetic pairwise comparisons indicated that the presence of interdental lamina is not associated with head size, mandible size and shape, and pubescence on the adductor interspace. We discuss the implications of our findings for the classification of Megachilini and the development of novel evolutionary, ecological, and functional hypotheses on this behavior. New taxa established are Pseudoheriadini Gonzalez & Engel, new tribe, Ochreriadini Gonzalez & Engel, new tribe, Cremnomegachile Gonzalez & Engel, new genus, Rozenapis Gonzalez & Engel, new genus, and Saucrochile Gonzalez & Engel, new genus, along with the following new combinations: Cremnomegachile dolichosoma (Benoist), new combination, Rozenapis ignita (Smith), new combination, and Saucrochile heriadiformis (Smith), new combination.

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Molecular systematic relationships and evidence for a recent origin of the thermal spring endemic snails Physella johnsoni and Physella wrighti (Pulmonata: Physidae)

Canadian Journal of Zoology ◽

10.1139/z01-154 ◽

2001 ◽

Vol 79 (11) ◽

pp. 1941-1950 ◽

Cited By ~ 3

Author(s):

Elpidio A Remigio ◽

Dwayne AW Lepitzki ◽

Jacqueline S Lee ◽

Paul DN Hebert

Keyword(s):

Large Subunit ◽

Sequence Divergence ◽

Thermal Spring ◽

Ancestral Population ◽

Molecular Systematic ◽

Sequence Comparisons ◽

Evolutionary Origins ◽

Species Pairs ◽

Tree Topologies ◽

Recent Origin

The evolutionary origins of Physella johnsoni and Physella wrighti, freshwater snails endemic to thermal springs in Alberta and British Columbia, were examined by sequence comparisons of mitochondrial genes coding for segments of the large subunit ribosomal RNA (16S) and cytochrome c oxidase I (COI) with those in the closely allied species Physella gyrina. Phylogenetic reconstructions based on combined and separate analyses of the datasets identified P. wrighti as the sister taxon to a P. johnsoni + P. gyrina clade. For both gene regions there was little or no sequence variation among conspecific individuals, but a number of diagnostic differences existed between each of the species pairs. Tree topologies and estimates of sequence divergence indicate that the divergence events which separated the three species occurred rather recently and at relatively brief intervals, and it is likely that P. wrighti is the source of the ancestral population from which P. johnsoni and P. gyrina were derived. Our findings support the recognition of P. johnsoni and P. wrighti as endemic species. The populations of P. johnsoni probably separated from P. gyrina about 10 000 years ago, when glaciers retreated from the Banff area and prehistoric lake levels dropped. The limited molecular divergence between P. johnsoni and P. gyrina argues against their current placement in different subgenera within the genus Physella.

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ON THE EPISTEMIC SIGNIFICANCE OF EVIDENCE YOU SHOULD HAVE HAD

Episteme ◽

10.1017/epi.2016.24 ◽

2016 ◽

Vol 13 (4) ◽

pp. 449-470 ◽

Cited By ~ 4

Author(s):

Sanford C. Goldberg

Keyword(s):

Strict Liability ◽

Full Range ◽

Higher Order ◽

The Other ◽

Total Evidence ◽

Knowing How ◽

The One ◽

Additional Support ◽

Higher Order Evidence

ABSTRACTElsewhere I and others have argued that evidence one should have had can bear on the justification of one's belief, in the form of defeating one's justification. In this paper, I am interested in knowing how evidence one should have had (on the one hand) and one's higher-order evidence (on the other) interact in determinations of the justification of belief. In doing so I aim to address two types of scenario that previous discussions have left open. In one type of scenario, there is a clash between a subject's higher-order evidence and the evidence she should have had: S's higher-order evidence is misleading as to the existence or likely epistemic bearing of further evidence she should have. In the other, while there is further evidence S should have had, this evidence would only have offered additional support for S's belief that p. The picture I offer derives from two “epistemic ceiling” principles linking evidence to justification: one's justification for the belief that p can be no higher than it is on one's total evidence, nor can it be higher than what it would have been had one had all of the evidence one should have had. Together, these two principles entail what I call the doctrine of Epistemic Strict Liability: insofar as one fails to have evidence one should have had, one is epistemically answerable to that evidence whatever reasons one happened to have regarding the likely epistemic bearing of that evidence. I suggest that such a position can account for the battery of intuitions elicited in the full range of cases I will be considering.

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Silica Incorporation in the Cell Wall of the Singing Cell of Urtica dioica

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100116541 ◽

1975 ◽

Vol 33 ◽

pp. 584-585

Author(s):

A. E. Sowers ◽

E. L. Thurston

Keyword(s):

Cell Wall ◽

Unique Feature ◽

Urtica Dioica ◽

Wall Material ◽

Pain Response ◽

Apical Portion ◽

Ultrastructural Investigation ◽

Plant Families ◽

Bulbous Tip

Plant stinging emergences exhibit functional similarities in that they all elicit a pain response upon contact. A stinging emergence consists of an elongated stinging cell and a multicellular pedestal (Fig. 1). A recent ultrastructural investigation of these structures has revealed the ontogeny and morphology of the stinging cells differs in representative genera in the four plant families which possess such structures. A unique feature of the stinging cell of Urtica dioica is the presence of a siliceous cell wall in the apical portion of the cell. This rigid region of the cell wall is responsible for producing the needle-like apparatus which penetrates the skin. The stinging cell differentiates the apical bulbous tip early in development and the cell continues growth by intercalary addition of non-silicified wall material until maturity.The uppermost region of the stinging cell wall is entirely composed of silica (Fig. 2, 3) and upon etching with a 3% solution of HF (5 seconds), the silica is partially removed revealing the wall consisting of individualized silica bodies (Fig. 4, 5).

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Time Block After Time Block

ASHA Leader ◽

10.1044/leader.ftr2.18082013.40 ◽

2013 ◽

Vol 18 (8) ◽

pp. 40-45 ◽

Cited By ~ 1

Author(s):

Judy Rudebusch ◽

JoAnn Wiechmann

Keyword(s):

Full Range ◽

Time Block ◽

School Based ◽

Schedule Activity

To offer a full range of RTI and IEP services, school-based SLPs can schedule activity blocks rather than go student by student—here's how.

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The Use of Neuroplastic Principles Affects the Swallow Motor Plan of a Patient in Severe Cognitive Decline: A Case Study

Perspectives of the ASHA Special Interest Groups ◽

10.1044/persp1.sig15.79 ◽

2016 ◽

Vol 1 (15) ◽

pp. 79-83

Author(s):

Ed Bice ◽

Kristine E. Galek

Keyword(s):

Central Nervous System ◽

Cognitive Decline ◽

Full Range ◽

Movement Speed ◽

Positive Outcomes ◽

Verbal Cues ◽

Motor Plan ◽

Bolus Size ◽

The Central Nervous System

Dysphagia is common in patients with dementia. Dysphagia occurs as a result of changes in the sensory and motor function of the swallow (Easterling, 2007). It is known that the central nervous system can undergo experience-dependent plasticity, even in those individuals with dementia (Park & Bischof, 2013). The purpose of this study was to explore whether or not the use of neuroplastic principles would improve the swallow motor plan and produce positive outcomes of a patient in severe cognitive decline. The disordered swallow motor plan was manipulated by focusing on a neuroplastic principles of frequency (repetition), velocity of movement (speed of presentation), reversibility (Use it or Lose it), specificity and adaptation, intensity (bolus size), and salience (Crary & Carnaby-Mann, 2008). After five therapeutic sessions, the patient progressed from holding solids in her mouth with decreased swallow initiation to independently consuming a regular diet with full range of liquids with no oral retention and no verbal cues.

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Further Validity of the Japanese Version of the Ten Item Personality Inventory (TIPI-J)

Journal of Individual Differences ◽

10.1027/1614-0001/a000145 ◽

2014 ◽

Vol 35 (4) ◽

pp. 236-244 ◽

Cited By ~ 16

Author(s):

Atsushi Oshio ◽

Shingo Abe ◽

Pino Cutrone ◽

Samuel D. Gosling

Keyword(s):

Big Five ◽

Content Validity ◽

Structural Equation ◽

English Language ◽

Full Range ◽

Reliability And Validity ◽

Japanese Version ◽

Personality Inventory ◽

Equation Modeling ◽

Big Five Personality

The Ten Item Personality Inventory (TIPI; Gosling, Rentfrow, & Swann, 2003 ) is a widely used very brief measure of the Big Five personality dimensions. Oshio, Abe, and Cutrone (2012) have developed a Japanese version of the TIPI (TIPI-J), which demonstrated acceptable levels of reliability and validity. Until now, all studies examining the validity of the TIPI-J have been conducted in the Japanese language; this reliance on a single language raises concerns about the instrument’s content validity because the instrument could demonstrate reliability (e.g., retest) and some forms of validity (e.g., convergent) but still not capture the full range of the dimensions as originally conceptualized in English. Therefore, to test the content validity of the Japanese TIPI with respect to the original Big Five formulation, we examine the convergence between scores on the TIPI-J and scores on the English-language Big Five Inventory (i.e., the BFI-E), an instrument specifically designed to optimize Big Five content coverage. Two-hundred and twenty-eight Japanese undergraduate students, who were all learning English, completed the two instruments. The results of correlation analyses and structural equation modeling demonstrate the theorized congruence between the TIPI-J and the BFI-E, supporting the content validity of the TIPI-J.

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