268,258 research outputs found
<i>Planolites</i> isp. burrows from Mud Buttes.
No full text<p>(A) Plan view showing undersides of closely packed horizontal burrows at coal/silty sandstone interface. Note coal still adherent to some burrows (specimen KT3/UCM 98212). (B) Discernible burrows colored and numbered to illustrate minimum burrow density within 8 cm<sup>2</sup> (specimen KT4/UCM 98213). Portions of at least 23 burrows comprise roughly 30% of area of white box. Burrows are colored different shades of green to illustrate overlapping relationships. The burrowing activity likely took place within a short period of time, but burrows colored darker green were lower in the soil profile and appear to have been crossed <i>in situ</i> by other burrows (lighter shades of green). Burrows colored lightest green were the topmost burrows. Note that this specimen is the same as that in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0070920#pone-0070920-g001" target="_blank">Figure 1D</a>. (C) Close-up of burrow 19 in B (specimen KT4/UCM 98213).</p
Let the Use of the Words Teach You Their Meaning:Sue MacLaine and Jonathan Burrows in dialogue
No full textA conversation between theatre maker Sue MacLaine and choreographer Jonathan Burrows on MacLaine's performance 'Can I Start Again Please' (2015), focussing on her use of Wittgenstein's ideas and her approaches to performance about trauma
Let the Use of the Words Teach You Their Meaning:Sue MacLaine and Jonathan Burrows in dialogue
No full textA conversation between theatre maker Sue MacLaine and choreographer Jonathan Burrows on MacLaine's performance 'Can I Start Again Please' (2015), focussing on her use of Wittgenstein's ideas and her approaches to performance about trauma
(L.) Burrows
No full textMacropore formation and litter incorporation are two results of earthworm [Lumbricus terrestris (L.)] activities that can influence trophic dynamics inside burrows. Thus, mesocosms were constructed to examine changes in microbial biomass and microfaunal communities inside artificial compared with earthworm burrows. Four treatments were established: (i) no worms (CTRL); (ii) unlined, artificial burrows (ARTF); (iii) corn (Zea mays L.) leaf litter-lined, artificial burrows (LEAF); and (iv) Lumbricus terrestris (L.) burrows (WORM). There were no consistent differences in community structures between unlined, artificial burrows and control soils during a 16-wk incubation. In contrast, protozoan numbers were elevated throughout the experiment in LEAF and WORM. A succession of nematode abundances occurred in LEAF, with plant parasitic and Tylenchid nematode numbers peaking at 5 wk, followed by high bacterivorous and fungivorous nematode numbers. In WORM, bacterivorous nematode numbers and active bacterial biomass were elevated for 1 and 3 wk, respectively, before declining. Active fungal biomass increased in WORM, whereas fungivorous nematodes were inhibited in earthworm burrows. While litter incorporation appeared to accelerate the rate of trophic interactions in artificial burrows, the effects of earthworms appeared to transcend that of litter translocation into soil, with earthworms differentially selecting for particular food web dynamics
Differential <i>Carcinus</i> survivorship with and without burrows access and predation exposure.
No full text<p>Tethered <i>Carcinus</i> with access to burrows to avoid desiccation and in cages to avoid predation experienced the highest survivorship, while those exposed to both stressors experienced significant mortality. These results underscore the role of <i>Sesarma</i> burrows as refuges from desiccation, which transform inhospitable die-off banks into benign intertidal habitats capable of sustaining large, burrow-dwelling <i>Carcinus</i> populations.</p
Burrows-Wheeler Transform on Purely Morphic Words
No full textThe study of the compressibility of repetitive sequences is an issue that is attracting great interest. We consider purely morphic words, which are highly repetitive sequences generated by iterating a morphism φ that admits a fixed point (denoted by φ^∞(a) ) starting from a given character a belonging to the finite alphabet A , i.e. φ^∞(a)=lim_{i→∞}φ^i(a) . Such morphisms are called prolongable on a . Here we focus on the compressibility via the Burrows-Wheeler Transform (BWT) of infinite families of finite sequences generated by morphisms. In particular, denoted by r(w) the number of equal-letter runs of a word w , we provide new upper bounds on r(bwt(φ^i(a))) , i.e. the number of equal-letter runs produced when BWT is applied on φ^i(a) . Such bounds depend on the factor complexity f_x(n) of the infinite word x=φ^∞(a) , that counts, for each n≥0 , the number of distinct factors of x having length n
Synapsid Burrows in the Lower Jurassic Navajo Sandstone, Utah
No full textEnigmatic structures below interdune deposits of the Lower Jurassic Navajo Sandstone near Moab, Utah are interpreted as synapsid burrows based on similar morphologies to fossil and extant synapsid burrows. Two types of burrows are distinguished by their size. Type I burrows are large diameter and comprise complex, high density sinuous tunnels, Y- and T- branched tunnels, sinuous ramps, and chambers. Type I burrows at one locality weather into mounds averaging 33 m x 22 m and extend ~ 1 m above the surface. Type I burrows are dorsoventrally flattened, in cross section averaging 9.3 cm wide and 4.2 cm high, and are sand filled and structureless. These burrows mostly have smooth walls, though some have scalloped walls. Type I burrows represent a new ichnogenera and ichnospecies Labyrinthopolis odieri. These burrows are best explained by multiple individuals living together in social groups similar to modern vole (social) and mole rats (eusocial), and likely represent permanent dwelling structures for foraging, nesting, hiding, and food storage. Type II burrows are mega diameter with simple, inclined tunnels ~ 35 cm wide and ~ 20 cm high, and exhibit well-preserved bilobate morphology along the underside of the tunnel. The walls preserve a series of 3 or 4 thin (~ 4-8 mm), inclined scratch marks from the upper part of the wall and along the floor. Type II burrows represents a new ichnogenera and ichnospecies Schemalitus psalihyponomes. Type II burrows were likely constructed by therapsids based on similarities to therapsid burrows found in South Africa and Antarctica, and likely represents a permanent shelter used for dwelling and brooding. Alternate excavators for Type I and II burrows are rejected by reviewing and comparing burrow morphologies of fossil and extant vertebrate groups because morphologies are consistent within the major groups in both fossil and extant vertebrates. Burrow morphologies reflect the tracemaker's anatomy, social structure, media consistency, and food availability
Use of burrows by the endangered pygmy blue-tongue lizard, Tiliqua adelaidensis (Scincidae)
No full textThe pygmy blue-tongue lizard, Tiliqua adelaidensis , had been considered extinct until its recent rediscovery near Burra in the mid-north of South Australia. The lizards apparently rely on spider burrows with a single entrance as refuge sites. In this paper we describe observations from all-day video recordings of the entrances of burrows occupied by lizards on 31 days across the spring and early summer of 1996. The lizards spent most of each day either retreated down the burrow or basking at the burrow entrance. Early in the season, when temperatures were cooler, lizards spent more of each day basking, and more of their basking time fully emerged from the burrow, than later in the season. Results are consistent with the hypothesis that the lizards thermoregulate by moving in and out of the burrow. Lizards also fed by making short excursions from the burrow, often to catch passing invertebrate prey, although they also fed on flowers early in spring. Later in the season lizards were more likely to vacate their burrows for longer times, or to move away from their burrows, and mating activity was observed when males approached burrows occupied by females. The observations suggest that pygmy blue-tongue lizards rely heavily on burrows for many activities, and that any conservation management scheme for this endangered species will rely on maintaining an adequate supply of burrows.Tim Milne, C. Michael Bull and Mark N. Hutchinso
<i>Polycylindrichnus</i>: possible Silurian tunicate burrows from southern Ontario
No full text Several specimens of a new trace fossil, Polycylindrichnus prolifer, n. gen., n. sp., have been collected from the Middle Silurian Thorold Formation in Hamilton, Ontario. Traces are multiple burrows, originating from a common source at depth, budding into several cylindrical to conical, subhorizontal burrows. Burrow openings lie on a common bedding plane. Traces are tentatively attributed to the activities of infaunal tunicates. </jats:p
Relatedness of individuals within burrows.
No full text<p>Mean (±1SE) relatedness coefficient, R [43], for 22 burrows containing two or more individual <i>P. vlangalii</i>. The dashed line indicates the overall mean burrow relatedness while the solid line is the population mean relatedness.</p
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