scholarly journals A new Colombian species of Liodessus diving beetles from the Páramo de Sumapaz (Coleoptera, Dytiscidae, Bidessini)

ZooKeys ◽  
2021 ◽  
Vol 1059 ◽  
pp. 79-87
Author(s):  
Michael Balke ◽  
Yoandri Suarez-Megna ◽  
Rodulfo Ospina-Torres ◽  
Juan Simon Venegas ◽  
Carlos Prieto ◽  
...  

Liodessus picinussp. nov. is described from the Páramo de Sumapaz near Bogota D.C. at 3,500 m above sea level. The species can be distinguished from the other Colombian Liodessus species by its dark coloration, discontinuous habitus, shiny surface of the pronotum and elytron, presence of a distinct occipital line, distinct basal pronotal striae, short or even faint basal elytral striae, as well as by its distinct geographic distribution and cox1 signature.

1975 ◽  
Vol 26 ◽  
pp. 395-407
Author(s):  
S. Henriksen

The first question to be answered, in seeking coordinate systems for geodynamics, is: what is geodynamics? The answer is, of course, that geodynamics is that part of geophysics which is concerned with movements of the Earth, as opposed to geostatics which is the physics of the stationary Earth. But as far as we know, there is no stationary Earth – epur sic monere. So geodynamics is actually coextensive with geophysics, and coordinate systems suitable for the one should be suitable for the other. At the present time, there are not many coordinate systems, if any, that can be identified with a static Earth. Certainly the only coordinate of aeronomic (atmospheric) interest is the height, and this is usually either as geodynamic height or as pressure. In oceanology, the most important coordinate is depth, and this, like heights in the atmosphere, is expressed as metric depth from mean sea level, as geodynamic depth, or as pressure. Only for the earth do we find “static” systems in use, ana even here there is real question as to whether the systems are dynamic or static. So it would seem that our answer to the question, of what kind, of coordinate systems are we seeking, must be that we are looking for the same systems as are used in geophysics, and these systems are dynamic in nature already – that is, their definition involvestime.


Paleobiology ◽  
2021 ◽  
Vol 47 (2) ◽  
pp. 171-177
Author(s):  
James C. Lamsdell ◽  
Curtis R. Congreve

The burgeoning field of phylogenetic paleoecology (Lamsdell et al. 2017) represents a synthesis of the related but differently focused fields of macroecology (Brown 1995) and macroevolution (Stanley 1975). Through a combination of the data and methods of both disciplines, phylogenetic paleoecology leverages phylogenetic theory and quantitative paleoecology to explain the temporal and spatial variation in species diversity, distribution, and disparity. Phylogenetic paleoecology is ideally situated to elucidate many fundamental issues in evolutionary biology, including the generation of new phenotypes and occupation of previously unexploited environments; the nature of relationships among character change, ecology, and evolutionary rates; determinants of the geographic distribution of species and clades; and the underlying phylogenetic signal of ecological selectivity in extinctions and radiations. This is because phylogenetic paleoecology explicitly recognizes and incorporates the quasi-independent nature of evolutionary and ecological data as expressed in the dual biological hierarchies (Eldredge and Salthe 1984; Congreve et al. 2018; Fig. 1), incorporating both as covarying factors rather than focusing on one and treating the other as error within the dataset.


2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Matthias Prange ◽  
Thomas Wilke ◽  
Frank P. Wesselingh

Phytotaxa ◽  
2021 ◽  
Vol 500 (3) ◽  
pp. 179-200
Author(s):  
CELLINI CASTRO DE OLIVEIRA ◽  
ANDRÉ LAURÊNIO DE MELO ◽  
MARCOS JOSÉ DA SILVA

A synopsis of the genus Cnidoscolus is presented for the midwestern region of Brazil, which resulted from the analysis of about 1,200 specimens from 62 national and foreign herbaria, including type collections. Observations of populations in field were also made. Nine species are recognized, one of which, C. mcvaughii, is new to science. It is described and illustrated, and comments about its geographic distribution, morphological relationships, systematic position, phenology, and conservation status are provided, as well as images and a map. The other species are contrasted by a dichotomous key. Also, distributional information, maps, conservation evaluations, images and morphologically diagnoses are included. Eight synonymizations, one lectotypification, a neotypifcation, and the re-establishment of C. neglectus are proposed.


2015 ◽  
Vol 84 (1) ◽  
pp. 41
Author(s):  
Gianluca Rassati

The study was carried out from 2003 to 2011 with the aim of determining the responsiveness to acoustic stimulation, the distribution and the habitat preferences of <em>Picus canus</em> and <em>Picoides tridactylus</em> in Friuli-Venezia Giulia (NE Italy). <em>P. canus</em> resulted as being more responsive than <em>P. tridactylus</em> to conspecifics stimulation, responding in 13.23% of the points where a stimulus was emitted, against 7.65% of the other species. In both taxa, when there was a response, it was predominantly by the male birds. The most frequent type of response in <em>P. canus</em> was song, heard in 57.89% of the points, while for <em>P. tridactylus</em>, it was drumming, which was heard in 65.38% of the points. For both species (especially for P. tridactylus), a tendency was recorded to expand the range and to occupy new areas within the known range. <em>P. canus i</em>n Friuli-Venezia Giulia was found from altitudes close to the sea level up to the treeline (range 0-2000 m a.s.l.), while <em>P. tridactylus</em> was found in montane and subalpine woodlands (range 800- 2000 m a.s.l.). The observations of P. canus were obtained at a mean altitude of 977 m a.s.l. (± 402 SD), located in the altitudinal belt dominated by Fagus sylvatica L., which is present in more than half of the woodlands in which the woodpecker was found.<em> P. tridactylus</em> was discovered at a mean altitude of 1424 m a.s.l. (± 246 SD), located in the altitudinal belt dominated by Picea abies (L.) H. Karst., which is present in almost 90% of the woodlands in which this species was found. In some areas, densities of 0.67-2.26 territories/100 ha were obtained for<em> P. canus</em> and 0.16-0.40 territories/100 ha for <em>P. tridactylus.</em> In Friuli-Venezia Giulia, a population of 320-390 pairs of P. canus and 45-60 pairs of P. tridactylus has been estimated, with an approximate 15% increase of<em> P. canus</em> compared to the beginning of the century, and just over 60% for the other species. Finally, some aspects concerning conservation-related problems are reported.


2012 ◽  
Vol 8 (2) ◽  
pp. 1057-1088 ◽  
Author(s):  
P. C. Tzedakis ◽  
E. W. Wolff ◽  
L. C. Skinner ◽  
V. Brovkin ◽  
D. A. Hodell ◽  
...  

Abstract. Differences in the duration of interglacials have long been apparent in palaeoclimate records of the Late and Middle Pleistocene. However, a systematic evaluation of such differences has been hampered by the lack of a metric that can be applied consistently through time and by difficulties in separating the local from the global component in various proxies. This, in turn, means that a theoretical framework with predictive power for interglacial duration has remained elusive. Here we propose that the interval between the terminal oscillation of the bipolar-seesaw and three thousand years (kyr) before its first major reactivation provides an estimate that approximates the length of the sea-level highstand, a measure of interglacial duration. We apply this concept to interglacials of the last 800 kyr by using a recently-constructed record of interhemispheric variability. The onset of interglacials occurs within 2 kyr of the peak in boreal summer insolation and is consistent with the canonical view of Milankovitch forcing dictating the broad timing of interglacials. Glacial inception always takes place when obliquity is decreasing and never after the obliquity minimum. The phasing of precession and obliquity appears to influence the persistence of interglacial conditions over one or two insolation peaks, leading to shorter (~13 kyr) and longer (~28 kyr) interglacials. Glacial inception occurs approximately 10 kyr after peak interglacial conditions in temperature and CO2, representing an interglacial "relaxation" time over which gradual cooling takes place. Second-order differences in duration may be a function of stochasticity in the climate system, or small variations in background climate state and the magnitude of feedbacks and mechanisms contributing to glacial iinception, and as such, difficult to predict. On the other hand, the broad duration of an interglacial may be determined by the phasing of astronomical parameters and the history of insolation, rather than the instantaneous forcing strength at inception.


Author(s):  
David Beerling

By arriving at the South Pole on 14 December 1911, the Norwegian explorer Roald Amundsen (1872–1928) reached his destination over a month ahead of the British effort led by Captain Robert Falcon Scott (1868–1912). As Scott’s party approached the South Pole on 17 January 1912, they were devastated to see from afar the Norwegian’s black flag. On arrival, they discovered the remains of his camp with ski and sledge tracks, and numerous dog footprints. Amundsen, it turned out, had used dogs and diversionary tactics to secure victory while the British team had man-hauled their sledges. These differences were not lost on The Times in London, which marked the achievement with muted praise, declaring it ‘not quite in accordance with the spirit of fair and open competition which hitherto marked Antarctic exploration’. Exhausted, Scott and his men spent time the following day making scientific observations around the Pole, erected ‘our poor slighted Union Jack’, and photographed themselves in front of it (Plate 11). Lieutenant Bowers took the picture by pulling a string to activate the shutter. It is perhaps the most well known, and at the same time the saddest picture, of the entire expedition—a poignant image of the doomed party, all of whom look utterly fed up as if somehow sensing the fate awaiting them. The cold weather, icy wind, and dismal circumstances led Scott to acerbically remark in his diary: ‘Great god! This is an awful place and terrible enough to have laboured to it without the reward of priority.’ By this time, the party had been hauling their sledges for weeks, and all the men were suffering from dehydration, owing to fatigue and altitude sickness from being on the Antarctic plateau that sits nearly 3000m above sea level. Three of them, Captain Oates, Seaman Evans, and Bowers, were badly afflicted with frostbitten noses and cheeks. Ahead lay the return leg, made all the more unbearable by the crippling psychological blow of knowing they had been second to the Pole. After a gruelling 21-day trek in bitterly cold summit winds, the team reached their first cache of food and fuel, covering the distance six days faster than it had taken them to do the leg in the other direction.


Author(s):  
Bruce A. Stein ◽  
Larry E. Morse

The Carolina hemlock (Tsuga caroliniana) survives in just a few rocky streambeds along the lower slopes of the Blue Ridge Mountains. Other species of hemlock abound across the United States, but none bear a close resemblance to this particular tree. The closest relatives of the Carolina hemlock, in fact, survive in only one other forest on Earth, some 7,000 miles away in Hubei province of eastern China. The forests of eastern Asia and eastern North America are so similar that if you were suddenly transported from one to the other, you would be hard-pressed to tell them apart. In the swift mountain streams rushing past these seemingly displaced hemlocks live a number of small, colorful fish known as darters. Darters are found only in North America and have evolved into a prolific variety of fishes. Up to 175 species inhabit U.S. waters, including the famous snail darter (Percina tanasi), which brought endangered species issues to the fore when it held up construction of the Tellico Dam on the Little Tennessee River. How is it that these two organisms, hemlock and darter, one with its closest relatives on the other side of the globe and the other found nowhere else in the world, came to be living side by side? Just how many plants and animals share the piece of Earth that we know as the United States of America? Why these and not others? These are central questions for understanding the diversity of the nation’s living resources. The United States encompasses an enormous piece of geography. With more than 3.5 million square miles of land and 12,000 miles of coastline, it is the fourth largest country on Earth, surpassed only by Russia, Canada, and China. The nation spans nearly a third of the globe, extending more than 120 degrees of longitude from eastern Maine to the tip of the Aleutian chain, and 50 degrees in latitude from Point Barrow above the Arctic Circle to the southern tip of Hawaii below the tropic of Cancer. This expanse of terrain includes an exceptional variety of topographic features, from Death Valley at 282 feet below sea level to Mt. McKinley at 20,320 feet above sea level.


1971 ◽  
Vol 13 ◽  
pp. 153-159 ◽  
Author(s):  
A. F. Cook ◽  
C. L. Hemenway ◽  
P. M. Millman ◽  
A. Swider

An extraordinary spectrum of a meteor at a velocity of about 18.5±1.0 km s-1 (approximate uncertainty) was observed from the Springhill Meteor Observatory with an image-orthicon camera at 1970 August 10 d2h 48m 518 UT. The radiant of the meteor was at an altitude of about 49°. It was first seen shoioing a yellow-red continuous spectrum alone at a height of 137±8 km (estimated uncertainty) which we ascribe to the first positive group of nitrogen bands. At 1.608 after its initial appearance the meteor had descended to 116±6 km above sea-level when it brightened rapidly from its previous threshold brighness into a uniform continuum. After a further 0.738 at a height of 106±6 km the D-line of neutral sodium appeared and 0.148 later (height 105±5 km) all the other lines of the spectrum also appeared. The continuum remained dominant to the end 0.408 later (height 87±5 km) or 3.878 after initial appearance.Water of hydration and entrained carbon flakes of characteristic dimension about 0.2 micron or less are proposed as constituents of the meteoroid to explain these phenomena.


2020 ◽  
Vol 298 (2) ◽  
pp. 137-146
Author(s):  
Günter Schweigert

The Late Jurassic nautiloid Somalinautilus antiquus (Dacqué, 1910), previously only known by the holotype from Lower Kimmeridgian strata of Ethiopia, is reported from the Lower Kimmeridgian (Platynota Zone) of Southern Germany. This unexpected record largely expands the known geographic distribution of this species. Another species of Somalinautilus, S. clavifer Tintant , 1994, is recorded for the first time from the Middle Jurassic (Lower Bathonian, Zigzag Zone) of Southern Germany. A short stratigraphic and palaeogeographic review of Somalinautilus occurrences is provided. Faunal migrations of nautiloids over large distances were probably triggered by sea- level highstands and/or palaeocurrents.


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