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Graphical evidence for the solar coronal structure during the Maunder minimum: comparative study of the total eclipse drawings in 1706 and 1715
We discuss the significant implications of three eye-witness drawings of the total solar eclipse on 1706 May 12 in comparison with two on 1715 May 3, for our understanding of space climate change. These events took place just after what has been termed the âdeep Maunder Minimumâ but fall within the âextended Maunder Minimumâ being in an interval when the sunspot numbers start to recover. Maria Clara Eimmertâs image in 1706 is particularly important because she was both a highly accomplished astronomical observer and an excellent artist: it was thought lost and was only re- discovered in 2012. Being the earliest coronal drawings of observational value yet identified, these drawings corroborate verbal accounts a corona without significant streamers, seen at totality of this and another eclipse event in 1652 during the Maunder Minimum. The graphical evidence implies that the coronal solar magnetic field was not lost but significantly weakened and the lack of coronal structure means there was little discernable open flux (either polar or at lower latitudes) even during the recovery phase of the Maunder Minimum. These observations provide evidence for a different state of oscillation of the solar dynamo and hence behaviour of the Sun in comparison with that during normal solar cycle minima (when a streamer belt between two polar coronal holes is visible) or near normal sunspot maxima (when coronal structure is caused by coronal holes at all latitudes) even to observers without a telescope
Major issues in the origins of rayâfinned fish ( A ctinopterygii) biodiversity
Rayâfinned fishes ( A ctinopterygii) dominate modern aquatic ecosystems and are represented by over 32000 extant species. The vast majority of living actinopterygians are teleosts; their success is often attributed to a genome duplication event or morphological novelties. The remainder are âliving fossilsâ belonging to a few depauperate lineages with longâretained ecomorphologies: P olypteriformes (bichirs), H olostei (bowfin and gar) and C hondrostei (paddlefish and sturgeon). Despite over a century of systematic work, the circumstances surrounding the origins of these clades, as well as their basic interrelationships and diagnoses, have been largely mired in uncertainty. Here, I review the systematics and characteristics of these major rayâfinned fish clades, and the early fossil record of A ctinopterygii, in order to gauge the sources of doubt. Recent relaxed molecular clock studies have pushed the origins of actinopterygian crown clades to the midâlate P alaeozoic [ S ilurianâ C arboniferous; 420 to 298 million years ago ( M a)], despite a diagnostic body fossil record extending only to the later M esozoic (251 to 66 M a). This disjunct, recently termed the â T eleost G apâ (although it affects all crown lineages), is based partly on calibrations from potential P alaeozoic stemâtaxa and thus has been attributed to poor fossil sampling. Actinopterygian fossils of appropriate ages are usually abundant and well preserved, yet longâterm neglect of this record in both taxonomic and systematic studies has exacerbated the gaps and obscured potential synapomorphies. At the moment, it is possible that later P alaeozoicâage teleost, holostean, chondrostean and/or polypteriform crown taxa sit unrecognized in museum drawers. However, it is equally likely that the â T eleost G apâ is an artifact of incorrect attributions to extant lineages, overwriting both a postâ P alaeozoic crown actinopterygian radiation and the ecomorphological diversity of stemâtaxa.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/109271/1/brv12086.pd
Com o diabo no corpo: os terrĂveis papagaios do Brasil colĂŽnia
Desde a Antiguidade, papagaios, periquitos e afins (Psittacidae) fascinaram os europeus por seu vivo colorido e uma notĂĄvel capacidade de interação com seres humanos. A descoberta do Novo Mundo nada faria alĂ©m de acrescentar novos elementos ao trĂĄfico de animais exĂłticos hĂĄ muito estabelecido pelos europeus com a Ăfrica e o Oriente. Sem possuir grandes mamĂferos, a AmĂ©rica tropical participaria desse comĂ©rcio com o que tinha de mais atrativo, essencialmente felinos, primatas e aves - em particular os papagaios, os quais eram embarcados em bom nĂșmero. Contudo, a julgar pelos documentos do Brasil colĂŽnia, esses volĂĄteis podiam inspirar muito pouca simpatia, pois nenhum outro animal - exceto as formigas - foi tantas vezes mencionado como praga para a agricultura. AlĂ©m disso, alguns psitĂĄcidas mostravam-se tĂŁo loquazes que inspiravam a sĂ©ria desconfiança de serem animais demonĂacos ou possessos, pois sĂł trĂȘs classes de entidades - anjos, homens e demĂŽnios - possuĂam o dom da palavra. Nos dias de hoje, vĂĄrios representantes dos Psittacidae ainda constituem uma ameaça para a agricultura, enquanto os indivĂduos muito faladores continuam despertando a suspeita de estarem possuĂdos pelo demĂŽnio. Transcendendo a mera curiosidade, essa crença exemplifica o quĂŁo intrincadas podem ser as relaçÔes do homem com o chamado âmundo naturalâ, revelando um universo mais amplo e multifacetado do que se poderia supor a princĂpio. Nesse sentido, a existĂȘncia de aves capazes de falar torna essa relação ainda mais complexa e evidencia que as dificuldades de estabelecer o limite entre o animal e o humano se estendem alĂ©m dos primatas e envolvem as mais inusitadas espĂ©cies zoolĂłgicas.Since ancient times, parrots and their allies (Psittacidae) have fascinated Europeans by their striking colors and notable ability to interact with human beings. The discovery of the New World added new species to the international exotic animal trade, which for many centuries had brought beasts to Europe from Africa and the Orient. Lacking large mammals, tropical America participated in this trade with its most appealing species, essentially felines, primates and birds - especially parrots - which were shipped in large numbers. It should be noted, however, that at times these birds were not well liked. In fact, according to documents from colonial Brazil, only the ants rank higher than parrots as the animals most often mentioned as agricultural pests. On the other hand, some of these birds were so chatty that people suspected them to be demonic or possessed animals, since only three classes of beings - angels, men and demons - have the ability to speak. Nowadays, several Psittacidae still constitute a threat to agriculture, and the suspicion that extremely talkative birds were demon possessed has also survived. More than a joke or a mere curiosity, this belief exemplifies how intricate manâs relationships with the ânatural worldâ may be. In this sense, the existence of birds that are able to speak adds a further twist to these relationships, demonstrating that the problem of establishing a boundary between the animal and the human does not only involve primates, but also includes some unusual zoological species
Francisci Willughbeii de Middleton in agro Warwicensi, armigeri, e Regia societate, Ornithologiae libri tres : in quibus aves omnes hactenus cognitae in methodum naturis suis convenientem redactae accurate describuntur, descriptiones iconibus elegantissimis & vivarum avium simillimis, aeri incisis illustrantur
totum opus recognovit, digessit, supplevit Joannes Raius ; sumptus in chalcographos fecit illustriss. D. Emma Willughby, viduaTitre impr. en rouge et noir dans un encadrement (double filet)Vignette au titre gravĂ©e sur cuivre (armes de la Royal Society)Illustration (taille-douce ; 17e siĂšcle) ; pl. num. I-LXXVII, non sign. exceptĂ© six planches portant la signature de W. Sherwin, F.H. van Houe et W. FaithorneSignatures : [ ]ÂČ a⎠A-QqâŽInde
Francisci Willughbeii De Middleton ... OrnithologiĂŠ Libri Tres : In quibus Aves Omnes hactenus cognitĂŠ In Methodum Naturis Suis convenientem redactĂŠ Accurate Describuntur ; Descriptiones Iconibus elegantissimis et vivarum Avium simillimis, Ări incisis illustrantur : Descriptiones Iconibus Elegantissimus Et Vivarum Avium simillimis, Aeri incisis illustrantur
Totum Opus recognovit, digessit, supplevit Joannes RaiusTitelseite mit EinfassungAus dem Vorbesitz der Naturforschenden Gesellschaft in ZĂŒrich (Exemplar ZB ZĂŒrich; NNN 90 | G
Leonard Baldner, Seventeenth Century Sportsman and Naturalist. An Unrecorded Copy of His Book, Containing His Portrait
The ornithology of Francis Willughby of Middleton in the county of Warwick Esq, fellow of the Royal Society in three books : wherein all the birds hitherto known, being reduced into a method sutable to their natures, are accurately described : the descriptions illustrated by most elegant figures, nearly resembling the live birds, engraven in LXXVII copper plates : translated into English, and enlarged with many additions throughout the whole work : to which are added, Three considerable discourses, I. of the art of fowling, with a description of several nets in two large copper plates, II. of the ordering of singing birds, III. of falconry / by John Ray ...
Desfontaines\u27s M\ue9moire sur quelques nouvelles esp\ue8ces d\u27oiseaux des c\uf4tes de Barbarie.
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