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Spatiotemporal dynamics in butterfly hybrid zones

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Insect Science 2024年第2期31卷 328-353页

作者： Ananda R.Pereira Martins Natalie B.Warren W.Owen McMillan Rowan D.H.Barrett Redpath Museum McGill University859 Sherbrooke Street WestMontrealQuebecCanada smithsonian Tropical ResearchInstitute GamboaPanama CityPanama

Evaluating whether hybrid zones are stable or mobile can provide novelinsights for evolution and conservation biology. Butterflies exhibit high sensitivity to envi-ronmental changes and represent an important model system for the study of hybrid zoneorigins and maintenance. Here, we review the literature exploring butterfly hybrid zones,with a special focus on their spatiotemporal dynamics and the potential mechanisms thatcould lead to their movement or stability. We then compare different lines of evidenceused to investigate hybrid zone dynamics and discuss the strengths and weaknesses ofeach approach. Our goal with this review is to reveal general conditions associated withthe stability or mobility of butterfly hybrid zones by synthesizing evidence obtained us-ing different types of data sampled across multiple regions and spatial scales. Finally, wediscuss spatiotemporal dynamics in the context of a speciation/divergence continuum, therelevance of hybrid zones for conservation biology, and recommend key topics for futureinvestigation.

关键词： butterflies human impacts hybrid zones movement spatiotemporaldynamics stability

The magnetosheath at high spectral resolution

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Earth and Planetary Physics 2024年第1期8卷 234-246页

作者： K.D.Küntz D.Koutroumpa W.R.Dunn A.Foster F.S.Porter D.G.Sibeck B.Walsh The Henry A.Rowland Department of Physics and Astronomy Johns Hopkins University3701 San Martin DriveBaltimoreMD21218USA NASA Goddard Space Flight Center 8800 Greenbelt RoadGreenbeltMD 20771USA LATMOS-OVSQ CNRSUVSQ Paris-SaclaySorbonne Université11 Boulevard d’Alembert78280GuyancourtFrance Department of Physics and Astronomy University College LondonLondonUK The Centre for Planetary Science at UCL/Birkbeck Gower StreetLondon WC1E 6BTUK Center for Astrophysics Harvard University&Smithsonian Institution60 Garden StreetCambridgeMA 02138USA Center for Space Physics Boston University110 Cummington MallBostonMAUSA

While we eagerly anticipate SMILE’s(Solar wind Magnetosphere Ionosphere Link Explorer)unprecedented X-ray observations of the Earth’s magnetosheath and the initiation of a new era of magnetospheric research,it seems appropriate to look ahead to the abilities of the next generation of astrophysics *** these,the Line Emission Mapper(LEM),a large aperture micro-calorimeter based mission,is currently planned to be able to observe the magnetosheath at high spectral resolution(~2 eV).With a field of view of~30′,LEM will allow higher spatial resolution and higher cadence measurement of the motion of a very small portion of the magnetopause over relatively short periods of time(multiple hours),complementing SMILE’s global ***’s strength is its spectral *** will be able to measure the abundance of a broad range of elements and ionization states,many of which are inaccessible to current in situ instruments,and will be able to separate the emission from the magnetosheath from the emission from the cosmic X-ray background using the difference in their relative velocities.

关键词： magnetosheath charge exchange solar wind abundances

Contributions of forensic anthropology to positive scientific identification:a critical Review

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Forensic Sciences Research 2019年第1期4卷 45-50页

作者： Douglas H.Ubelaker Austin Shamlou Amanda Kunkle Department of Anthropology Smithsonian InstitutionWashingtonDCUSA

This review covers previous and current literature on the impact of forensic anthropologists on the positive scientific identification of human remains and aims to provide an under-standing of what information a forensic anthropologist can contribute to an investigation. Forensic anthropologists looking to identify human remains study traits of the skeleton and any orthopedic devices present. In order to obtain a positive scientific identification, evi-dence that is both sufficiently unique to the individual and comparable to available ante-mortem data from that individual must be found. The increased availability of radiographs, scans and implants in recent decades has facilitated the identification process. When these records are unavailable, other techniques, such as craniofacial superimposition and facial approximation, can be employed. While these methods may assist the identification process, they are most useful for exclusion of certain individuals and gathering leads from the public. Forensic anthropologists have heavily relied on the skull and its complexities for identifica-tion – typically focusing on the frontal sinus and other unique traits. Post-cranial remains can provide important information about bone density, possible disease and other character-istics that may also be utilized. Techniques used to positively identify individuals are not limited to medicolegal death investigations, and have been useful in other legal contexts. In the future, a team approach, utilizing all the information gathered by multiple forensic scientists–including forensic anthropologists–will most likely become more common.

关键词： Forensic sciences forensic anthropology positive scientific identification medicolegal death investigation craniofacial superimposition facial approximation team approach

Estimation of age in forensic anthropology:historical perspective and recent methodological advances

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Forensic Sciences Research 2019年第1期4卷 1-9页

作者： Douglas H.Ubelaker Haley Khosrowshahi Department of Anthropology Smithsonian InstitutionWashingtonDCUSA

Estimation of age represents a central focus of forensic anthropological analysis of human skeletal remains and of the living. Advances registered in recent research include the topics of taphonomic impact, new anatomical areas of interest, histology, population variation, the dental pulp chamber, technology, mathematical approaches, biochemical analysis and techniques specifically targeting the living. This article reviews the historical development of age estimation methods and considers likely future directions.

关键词： Age estimation forensic sciences forensic anthropology history recent advances

Female mate choice and the potential for ornament evolution in túngara frogs Physalaemus pustulosus

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Current Zoology 2010年第3期56卷 343-357页

作者： Michael J.RYAN Ximena E.BERNAL A.Stanley RAND Section of Integrative Biology C0930 University of Texas smithsonian Tropical Research institution Department of Biological Science Texas Tech University Srnithsonian Tropical Research institution

The potential for ornament evolution in response to sexual selection rests on the interaction between the permissive- ness or selectivity of female preferences and the constraints on male development of signaling related traits. We investigate the former by determining how latent female preferences either exaggerate the magnitude of current traits （i.e. elaborations） or favor novel traits （i.e. innovations）. In tt^ngara frogs, females prefer complex mating calls （whine-chucks） to simple calls （whine only）. The whine is critical for mate recognition while the chuck further enhances the attractiveness of the call. Here we use a combina- tion of synthetic and natural stimuli to examine latent female preferences. Our results show that a diversity of stimuli, including conspecific and heterospecific calls as well as predator-produced and human-made sounds, increase the attractiveness of a call when added to a whine. These stimuli do not make simple calls more attractive than a whine-chuck, however. In rare cases we found stimuli that added to the whine decrease the attractiveness of the call. Overall, females show strong preferences for both elaborations and innovations of the chuck. We argue that the emancipation of these acoustic adornments from mate recognition allows such female permissiveness, and that male constraints on signal evolution are probably more important in explaining why males evolved their specific adornment. Experimentally probing latent female preferences for stimuli out of the species＇ range is a useful means to gain insights about the potential of female choice to influence signal evolution and thus the astounding diversity in male sexually-selected traits [Current Zoology 56 （3）： 343-357, 2010].

关键词： Mate choice Ornament evolution Tfingara frogs Physalaemus pustulosus

Fragment analysis in forensic anthropology

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Forensic Sciences Research 2020年第4期5卷 260-265页

作者： Douglas H.Ubelaker Yaohan Wu National Museum of Natural History Smithsonian InstitutionWashingtonDCUSA

Anthropological analysis of fragmentary evidence can be challenging but diverse methods allow substantial information to be *** electron microscopy/energy dispersive X-ray spectroscopy enables determination if bone and/or tooth tissue is *** radioimmunoassay or DNA analysis can establish the species *** analysis can assist in species determination and reveal information about thermal *** analysis with special reference to the modern bomb-curve can clarify the post-mortem *** should also be aware that DNA analysis not only can enable positive identification but assist in the evaluation of sex and age at death.

关键词： Forensic sciences forensic anthropology fragments radiocarbon

Materials and technology of Chinese jades dating to the Western Zhou period (1050―771 BCE)

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Science China(Technological Sciences) 2008年第4期51卷 467-480页

作者： Janet G DOUGLAS Department of Conservation and Scientific Research Freer Gallery of Art / Arthur M. Sackler Gallery Smithsonian Institution

Excavated jades dating to the Western Zhou period (1050―771 BCE) from the Xi’an area in Shaanxi Province, China, and contemporaneous jades in the collections of the Arthur M. Sackler Gallery at the smithsonian institution have been studied to learn about the jade and stone materials and how they were worked during the Western Zhou period. Materials identification was carried out using a combination of techniques such as Fourier-transform infrared spectroscopy and X-ray diffraction. Tool marks were studied using stereomicroscopy and examination of mold impressions using scanning electron microscopy. All of these objects were pro- duced through simple processes involving solid drilling, riffling, and sharp point abrasion; and no evidence was found for the use of rotary tools for incising or sawing.

关键词： jade nephrite stone China Western Zhou scanning electron microscopy materials technology tool marks

The impact of scavenging:perspective from casework in forensic anthropology

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Forensic Sciences Research 2020年第1期5卷 32-37页

作者： Douglas H.Ubelaker Cassandra M.DeGaglia Department of Anthropology National Museum of Natural HistorySmithsonian InstitutionWashingtonDCUSA

Forensic anthropology casework frequently encounters evidence of animal scavenging asso-ciated with fragmentation and loss of skeletal *** research demonstrates that patterns of destruction in bone can suggest the size and type of animal *** study analyzes 107 cases reported on by the first author at the smithsonian institution to investigate patterns of scavenging in forensic anthropology *** investigation reveals that the extent of scavenger impact varies across the body,but primarily is concen-trated in the central body *** extensive animal scavenging can limit analysis,some evidence of foul play can be preserved.

关键词： Forensic sciences forensic anthropology scaveng-ing casework

A New Fossil Scorpionfly(Insecta:Mecoptera:Holcorpidae) with Extremely Elongate Male Genitalia from Northeastern China

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Acta Geologica Sinica(English Edition) 2017年第3期91卷 797-805页

作者： LI Lei Chungkun SHIH WANG Chen REN Dong Key Lab of Insect Evolution and Environmental Changes Capital Normal University Department of Paleobiology National Museum of Natural HistorySmithsonian Institution

Since Holcorpa maculosa was first described in 1878, it has attracted lots of attention due to its extremely elongate abdominal segments from the sixth to the eighth. Fossil records of family Holcorpidae are very rare, comprising two species in one genus represented by three fossil specimens, resulting in limited knowledge on the structure and function of holcorpid＇s unique male organ, as well as its evolutionary relationship with other scorpionflies. Herein we describe a new genus with a new species, Conicholcorpa stigmosa gen. et sp. nov., of the Holcorpidae from the Middle Jurassic Jiulongshan Formation near Daohugou Village, Inner Mongolia, China. This is the first holcorpid documented from the Daohugou locality, albeit two previously reported species with extremely elongate male organs but deemed as Family Incertae sedis. C. stigmosa gen. et sp. nov. is the earliest holcorpid hitherto, extending its existence from the Early Eocene to the Middle Jurassic by 114 million years and providing one more early case of presenting exaggerated male body parts for sexual display and/or selection. Our analysis supports the sister relationship between Holcorpidae and Orthophlebiidae. Our results not only enhance our knowledge of the morphology of Holcorpidae but also elucidate the relationship of known species of this family.

关键词： Conicholcorpa Daohugou Holcorpidae Jiulongshan Formation Middle Jurassic