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991.
Richard J. Butler Paul M. Barrett Paul Kenrick Malcolm G. Penn 《Biological reviews of the Cambridge Philosophical Society》2009,84(1):73-89
The significance of co‐evolution over ecological timescales is well established, yet it remains unclear to what extent co‐evolutionary processes contribute to driving large‐scale evolutionary and ecological changes over geological timescales. Some of the most intriguing and pervasive long‐term co‐evolutionary hypotheses relate to proposed interactions between herbivorous non‐avian dinosaurs and Mesozoic plants, including cycads. Dinosaurs have been proposed as key dispersers of cycad seeds during the Mesozoic, and temporal variation in cycad diversity and abundance has been linked to dinosaur faunal changes. Here we assess the evidence for proposed hypotheses of trophic and evolutionary interactions between these two groups using diversity analyses, a new database of Cretaceous dinosaur and plant co‐occurrence data, and a geographical information system (GIS) as a visualisation tool. Phylogenetic evidence suggests that the origins of several key biological properties of cycads (e.g. toxins, bright‐coloured seeds) likely predated the origin of dinosaurs. Direct evidence of dinosaur–cycad interactions is lacking, but evidence from extant ecosystems suggests that dinosaurs may plausibly have acted as seed dispersers for cycads, although it is likely that other vertebrate groups (e.g. birds, early mammals) also played a role. Although the Late Triassic radiations of dinosaurs and cycads appear to have been approximately contemporaneous, few significant changes in dinosaur faunas coincide with the late Early Cretaceous cycad decline. No significant spatiotemporal associations between particular dinosaur groups and cycads can be identified – GIS visualisation reveals disparities between the spatiotemporal distributions of some dinosaur groups (e.g. sauropodomorphs) and cycads that are inconsistent with co‐evolutionary hypotheses. The available data provide no unequivocal support for any of the proposed co‐evolutionary interactions between cycads and herbivorous dinosaurs – diffuse co‐evolutionary scenarios that are proposed to operate over geological timescales are plausible, but such hypotheses need to be firmly grounded on direct evidence of interaction and may be difficult to support given the patchiness of the fossil record. 相似文献
992.
There are many types of evidence that provide information about methods for obtaining animal nutrients. Several researchers suggest that the main element to be considered is the skeletal representation of the different species identified in the faunal assemblage. This element must be associated to the animals’ age at death and the localisation of processing marks of the carcasses (both those of anthropic origin and those produced by carnivores). Occasionally, these marks coincide on the same point of the bone, giving cause for overlapping marks. These marks can be considered an aid more to identify the anthropic manner for obtaining animal recourses. However, these cases are very unusual at archaeological sites, and it is not always easy to identify which of the two predators has obtained the prey first. Through the experimental process presented in this article, we have observed diagnostic elements on overlapping marks that show the action sequence of the predators (hominids and carnivores) on carcasses. These experimental criteria were applied to different archaeological sites of the Lower and Middle Pleistocene in the Iberian Peninsula: Bolomor Cave (Valencia, Spain) and level TD10-1 and TD6-2 of Gran Dolina (Atapuerca, Burgos). In these assemblages, we were able to distinguish hunting and scavenging events through overlapping marks, providing a new element to the general interpretation of these sites. 相似文献
993.
在浙江省天目山自然保护区的溪流中采集到四种暗色丝孢菌,即东方小短带孢Brachydesmiella orientalis,木生杯粉孢Conioscypha lignicola,球孢棒梗孢Exserticlava globosa和团聚伞集胞球枝霉Peyronelina glomerulata。其中B.orientalis和Peyronelina glomerulata是中国新记录,E.globosa和P.glomerulata为中国大陆第一次报道。本文对这四个种的特征进行了描述。 相似文献
994.
目前我国共发现分枝管菌属的真菌4种,其中微小分枝管菌Henningsomyces minimus为中国首次报道,该种发现于广西壮族自治区的弄岗自然保护区和陇瑞自然保护区。根据中国的材料对该种进行了详细描述和显微结构绘图,给出了中国该属种类的检索表,并对其他三个种进行了概要描述。 相似文献
995.
996.
The genus Micatagla Argaman (Bradynobaenidae: Apterogyninae) is reviewed from Egypt, based on specimens collected from Wadi Allaqi (Aswan, Southern Egypt) and Kom Osheim (Fayoum) and those deposited in Egyptian insect collections as well as recorded data from the literature. A single species, Micatagla klugi (André), was previously recorded from Egypt. Micatagla allaqiensis
sp. n., Micatagla ezzati
sp. n. and Micatagla pseudorainerii
sp. n. are described here. Micatagla antropovi Pagliano is also newly recorded from the Egyptian fauna. An illustrated key and a faunistic list comprising all Micatagla species recorded from Egypt are given. 相似文献
997.
The genus Pseudorthocladius Goetghebuer, 1943 from China, including 12 species, is reviewed. Five new species, P. (P.) binarius
sp. n., P. (P.) cylindratus
sp. n., P. (P.) digitus
sp. n., P. (P.) ovatus
sp. n. and P. (P.) paucus
sp. n. are described and illustrated as adult males. P. (P.) cristagus Stur & Sæther, 2004, P. (P.) jintutridecima (Sasa, 1996), P. (P.) macrovirgatus Sæther & Sublette, 1983, P. (P.) morsei Sæther & Sublette, 1983, P. (P.) uniserratus Sæther & Sublette, 1983, P. (L.) wingoi Sæther & Sublette, 1983 are newly recorded in Oriental Region. A key to the males of Pseudorthocladius in China is presented. 相似文献
998.
Michael J. Miller Sumihiro Koyama Noritaka Mochioka Jun Aoyama Shun Watanabe Katsumi Tsukamoto 《Marine and Freshwater Behaviour and Physiology》2014,47(4):265-272
A nemichthyid eel apparently of the genus Avocettina was observed and video recorded during the day from a submersible operating above the deep western slope of the West Mariana Ridge at a depth of about 800?m. The eel was oriented vertically, head-upward, with its long-thin body held rigidly straight. It remained motionless for more than 1?min except for small constant oscillations of the tip of the tail. It showed no reaction to the presence of the approaching submersible until contacting it. This body position has been seen in nemichthyid eels previously by submersibles in the Atlantic, Pacific and Indian oceans. It is postulated to be a prey or predator detection tactic that optimizes the use of the visual or lateral line senses. It may also be an efficient way to maintain a position or to move slowly through the water column without disrupting sensory function. 相似文献
999.
Dinesh Chandra Sharma Mohd Sajid Khan M Salman Khan Rashmi Srivastava Ashwini Kumar Srivastava Ritu Shukla 《Bioinformation》2014,10(5):316-319
The occurrence of a large number of fossil woods having resemblance in anatomical features with the modern palm genus, Phoenix
L in Deccan Intertrappean fossil flora of Maastrichtian-Danian age (i. e. Late Cretaceous and Earliest Tertiary (65-67 my)) indicates
the most primitive record of date palm. Present discovery of biocompounds from fossil wood of Phoenix collected from Deccan
Intertrappean having affinity with the biocompounds known from modern plant further exemplify the earliest documentation of
Phoenix in Indian peninsula. 相似文献
1000.