The overabundance of the perfect and the restriction of evidentiality in Standard Azerbaijani: A diachronic study of -(y)Ib and -mIş

This article investigates the historical development and reorganization of variation in the individual cells of the Standard Azerbaijani perfect paradigms, a phenomenon known as overabundance (Thornton 2011, 2012). Unlike many previous examples of overabundance in the literature, the variation of the present perfect in Standard Azerbaijani applies to all the relevant verb lexemes in the language and shows no indication of developing verb classes. Rather, the present study argues that, (i) while there is an ongoing reorganization of this variation, it is along lines of specialization for paradigmatic oppositions in person marking, and (ii) this reorganization is attributable to analogical extension on the basis of structural asymmetries in the person-marking of the evidential paradigm. Differentiation by Person (Dmitriyev 1927, Əfəndiyeva 2005) is an inherent structural property of the Azerbaijani verb paradigm, manifested by analogical change. The synchronic asymmetries in the perfect paradigms are best explained as the result frequency-sensitive changes, i.e., lower frequency categories (but not lexemes) correlate with the persistence of variation

Editors' Note

A summary of the conference and proceedings volumes.

Diachronic morphology in sign languages: examples

Supplementary material (examples) for the chapter "Diachronic moprhology in sign languages

Microfluidic-like Fabrication of a Vanadium-Cured Bioadhesive by Mussels

To anchor in seashore habitats, mussels fabricate adhesive byssus fibers mechanically reinforced by protein-metal coordination mediated via 3,4-dihydroxyphenylalanine (DOPA) – providing a well-established role model for bio-inspired design of smart metallopolymers and underwater glues. However, currently, the mechanism by which metal ions are integrated as cross-links during byssus formation is completely unknown. Here, we investigated the byssus formation process, combining traditional and advanced methods to identify how and when metals are incorporated into the material. We discovered that mussels concentrate and store iron and vanadium ions in intracellular metal storage particles (MSPs) complexed with previously unknown catechol-based storage molecules. During thread formation, stockpiled secretory vesicles containing concentrated fluid proteins are mixed with MSPs within a complex microfluidic-like network of interconnected channels where they coalesce forming protein-metal bonds within the nascent byssus. These insights are important for bio-inspired materials design, but also from a biological and chemical perspective – the active accumulation and utilization of vanadium is extremely rare in nature.</p

Lacunae rostralis: A new structure on the rostrum of sailfish Istiophorus platypterus

Recent comparative studies of billfishes (Istiophoridae and Xiphiidae) have provided evidence of differences in the form and function of the rostra (bill) among species. Here, we report the discovery of a new structure, lacuna rostralis, on the rostra of sailfish Istiophorus platypterus, which is absent on the rostra of swordfish Xiphias gladius, striped marlin Kajikia audax and blue marlin Makaira nigricans. The lacunae rostralis are small cavities that contain teeth. They were found on the ventral rostrum surface of all I. platypterus specimens examined and dorsally in half of them. Ventrally, the lacunae rostralis were most prominent in the mid-section of the rostrum. Dorsally, they occurred closer to the tip. The density of lacunae rostralis increased towards the rostrum tip but, because they are smaller in size, the percentage of rostrum coverage decreased. The teeth located within the lacunae rostralis were found to be different in size, location and orientation from the previously identified micro-teeth of billfish. We propose two potential functions of the lacunae rostralis that both relate to the use of the bill in feeding: mechanoreception of prey before tapping it with the bill, and more efficient prey handling via the creation of suction, or physical grip

Lacunae rostralis: A new structure on the rostrum of sailfish Istiophorus platypterus

Recent comparative studies of billfishes (Istiophoridae and Xiphiidae) have provided evidence of differences in the form and function of the rostra (bill) among species. Here, we report the discovery of a new structure, lacuna rostralis, on the rostra of sailfish Istiophorus platypterus, which is absent on the rostra of swordfish Xiphias gladius, striped marlin Kajikia audax and blue marlin Makaira nigricans. The lacunae rostralis are small cavities that contain teeth. They were found on the ventral rostrum surface of all I. platypterus specimens examined and dorsally in half of them. Ventrally, the lacunae rostralis were most prominent in the mid-section of the rostrum. Dorsally, they occurred closer to the tip. The density of lacunae rostralis increased towards the rostrum tip but, because they are smaller in size, the percentage of rostrum coverage decreased. The teeth located within the lacunae rostralis were found to be different in size, location and orientation from the previously identified micro-teeth of billfish. We propose two potential functions of the lacunae rostralis that both relate to the use of the bill in feeding: mechanoreception of prey before tapping it with the bill and more efficient prey handling via the creation of suction, or physical grip.Peer Reviewe

The rostral micro‐tooth morphology of blue marlin, Makaira nigricans

Billfish rostra potentially have several functions, however, their role in feeding is unequivocal in some species. Recent work linked morphological variation in rostral micro‐teeth to differences in feeding behaviour in two billfish species, the striped marlin (Kajikia audax) and the sailfish (Istiophorus platypterus). Here, we present the rostral micro‐tooth morphology for a third billfish species, the blue marlin (Makaira nigricans), for which the use of the rostrum in feeding behaviour is still undocumented from systematic observations in the wild. We measured the micro‐teeth on rostrum‐tips of blue marlin, striped marlin and sailfish using a micro‐CT approach and compared the tooth morphology among the three species. This was done after an analysis of video recorded hunting behaviour of striped marlin and sailfish revealed that both species strike prey predominantly with the first third of the rostrum, which provided the justification to focus our analysis on the rostrum tips. In blue marlin, intact micro‐teeth were longer compared to striped marlin but not to sailfish. Blue marlin had a higher fraction of broken teeth than both striped marlin and sailfish, and broken teeth were distributed more evenly on the rostrum. Micro‐tooth regrowth was equally low in both marlin species, but higher in sailfish. Based on the differences and similarities in the micro‐tooth morphology between the billfish species, we discuss potential feeding related rostrum use in blue marlin. We put forward the hypothesis that blue marlin might use their rostra in high‐speed dashes as observed in striped marlin, rather than in the high‐precision rostral strikes described for sailfish, possibly focusing on larger prey organisms