Tangled banks, braided rivers, and complex hierarchies: beyond microevolution and macroevolution.

Ever since the Modern Synthesis, a debate about the relationship between microevolution and macroevolution has persisted-specifically, whether they are equivalent, distinct, or explain one another. How one answers these questions has become shorthand for a much broader set of theoretical debates in evolutionary biology. Here, we examine microevolution and macroevolution in the context of the vast proliferation of data, knowledge, and theory since the advent of the Modern Synthesis.

Inequality in science and the case for a new agenda.

The history of the scientific enterprise demonstrates that it has supported gender, identity, and racial inequity. Further, its institutions have allowed discrimination, harassment, and personal harm of racialized persons and women. This has resulted in a suboptimal and demographically narrow research and innovation system, a concomitant limited lens on research agendas, and less effective knowledge translation between science and society.

The Ideas Lab Concept, Assembling the Tree of Life, and AVAToL.

In August 2011, a week-long NSF-sponsored workshop focusing on the Tree of Life (ToL) took place in Lake Placid, New York. This workshop, called AVAToL (Assembling Visualizing, and Analyzing the Tree of Life), was the first application of NSF's Ideas Lab concept to systematics. In this article we outline the history and motivation for the Ideas Lab approach and its application to the ToL, explain the nuts and bolts of the Ideas Lab process and look to the potential contributions of AVAToL funded projects to help enable the future of ToL and more broadly, comparative biological research.

Finding the neck-trunk boundary in snakes: anteroposterior dissociation of myological characteristics in snakes and its implications for their neck and trunk body regionalization.

The neck and trunk regionalization of the presacral musculoskeletal system in snakes and other limb-reduced squamates was assessed based on observations on craniovertebral and body wall muscles. It was confirmed that myological features characterizing the neck in quadrupedal squamates (i.e.

Rejecting "the given" in systematics.

How morphology and systematics come together through morphological analysis, homology hypotheses and phylogenetic analysis is a topic of continuing debate. Some contemporary approaches reject biological evaluation of morphological characters and fall back on an atheoretical and putatively objective (but, in fact, phenetic) approach that defers to the test of congruence for homology assessment. We note persistent trends toward an uncritical empiricism (where evidence is believed to be immediately "given" in putatively theory-free observation) and instrumentalism (where hypotheses of primary homology become mere instruments with little or no empirical foundation for choosing among competing phylogenetic hypotheses).

Cranial anatomy of the spade-headed amphisbaenian Diplometopon zarudnyi (Squamata, Amphisbaenia) based on high-resolution X-ray computed tomography.

The skull of the trogonophid amphisbaenian Diplometopon zarudnyi is described from high-resolution X-ray computed tomographic (HRXCT) imagery of a whole museum specimen preserved in ETOH. The skull was digitally resliced and disarticulated into individual elements, producing novel visualizations that allow detailed morphological analysis of its three-dimensionally complex structure. The prefrontal and jugal are absent in Diplometopon.

Cranial anatomy of the extinct amphisbaenian Rhineura hatcherii (Squamata, Amphisbaenia) based on high-resolution X-ray computed tomography.

The fossilized skull of a small extinct amphisbaenian referable to Rhineura hatcherii Baur is described from high-resolution X-ray computed tomographic (HRXCT) imagery of a well-preserved mature specimen from the Brule Formation of Badlands National Park, South Dakota. Marked density contrast between bones and surrounding matrix and at bone-to-bone sutures enabled the digital disarticulation of individual skull elements. These novel visualizations provide insight into the otherwise inaccessible three-dimensionally complex structure of the bones of the skull and their relationships to one another, and to the internal cavities and passageways that they enclose.

Repeated evolution of limblessness and digging heads in worm lizards revealed by DNA from old bones.

The evolutionary relationships of the burrowing amphisbaenians ('worm lizards') have long been controversial for several reasons: the rarity of museum specimens available for study, highly derived morphological conditions that can confound comparative studies and difficulty in obtaining tissues for molecular phylogenetic studies because of their secretive habits in the wild. We present a phylogenetic analysis of two nuclear genes obtained from both fresh tissues and museum specimens of worm lizards. We achieved sufficient taxonomic sampling for analysis by extracting DNA from museum specimens using a modified forensics protocol.