What bugged the dinosaurs? Poinar, George O; Poinar, Roberta
2008, 2010., 20100101, 2010, 2008-01-01
eBook, Book
Millions of years ago in the Cretaceous period, the mighty Tyrannosaurus rex--with its dagger-like teeth for tearing its prey to ribbons--was undoubtedly the fiercest carnivore to roam the Earth. Yet ...asWhat Bugged the Dinosaurs?reveals, T. rex was not the only killer. George and Roberta Poinar show how insects--from biting sand flies to disease-causing parasites--dominated life on the planet and played a significant role in the life and death of the dinosaurs.
The Poinars bring the age of the dinosaurs marvelously to life. Analyzing exotic insects fossilized in Cretaceous amber at three major deposits in Lebanon, Burma, and Canada, they reconstruct the complex ecology of a hostile prehistoric world inhabited by voracious swarms of insects. The Poinars draw upon tantalizing new evidence from their amazing discoveries of disease-producing vertebrate pathogens in Cretaceous blood-sucking flies, as well as intestinal worms and protozoa found in fossilized dinosaur excrement, to provide a unique view of how insects infected with malaria, leishmania, and other pathogens, together with intestinal parasites, could have devastated dinosaur populations.
A scientific adventure story from the authors whose research inspiredJurassic Park,What Bugged the Dinosaurs?? offers compelling evidence of how insects directly and indirectly contributed to the dinosaurs' demise.
Paleoophiocordyceps coccophagus, a fungal parasite of a scale insect from the Early Cretaceous (Upper Albian), is reported and described here. This fossil not only provides the oldest fossil evidence ...of animal parasitism by fungi but also contains morphological features similar to asexual states of
Hirsutella and
Hymenostilbe of the extant genus
Ophiocordyceps (Ophiocordycipitaceae, Hypocreales, Sordariomycetes, Pezizomycotina, Ascomycota). Because species of Hypocreales collectively exhibit a broad range of nutritional modes and symbioses involving plants, animals and other fungi, we conducted ancestral host reconstruction coupled with phylogenetic dating analyses calibrated with
P.
coccophagus. These results support a plant-based ancestral nutritional mode for Hypocreales, which then diversified ecologically through a dynamic process of intra- and interkingdom host shifts involving fungal, higher plant and animal hosts. This is especially evident in the families Cordycipitaceae, Clavicipitaceae and Ophiocordycipitaceae, which are characterized by a high occurrence of insect pathogens. The ancestral ecologies of Clavicipitaceae and Ophiocordycipitaceae are inferred to be animal pathogens, a trait inherited from a common ancestor, whereas the ancestral host affiliation of Cordycipitaceae was not resolved. Phylogenetic dating supports both a Jurassic origin of fungal–animal symbioses within Hypocreales and parallel diversification of all three insect pathogenic families during the Cretaceous, concurrent with the diversification of insects and angiosperms.
An ambrosia fungus is described from filamentous sporodochia adjacent to a wood–boring ambrosia beetle (Coleoptera: Curculionidae: Platypodinae) in mid-Cretaceous Burmese amber. Yeast-like propagules ...and hyphal fragments of Paleoambrosia entomophila gen. nov. et sp. nov. occur in glandular sac mycangia located inside the femur of the beetle. This is the first record of a fossil ambrosia fungus, showing that symbiotic associations between wood–boring insects and ectosymbiotic fungi date back some 100 million years ago. The present finding moves the origin of fungus-growing by insects from the Oligocene to the mid-Cretaceous and suggests a Gondwanan origin.
This chapter discusses the evolutionary history of nematode parasites of invertebrates, vertebrates and plants based on fossil remains in amber, stone and coprolites dating from the Palaeozoic to the ...Holocene. The earliest parasitic nematode is a primitive plant parasite from the Devonian. Fossil invertebrate-parasitic nematodes first appeared in the Early Cretaceous, while the earliest fossil vertebrate-parasitic nematodes are from Upper Triassic coprolites. Specific examples of fossil nematode parasites over time are presented, along with views on the origin and evolution of nematodes and their hosts.
Mermithid nematodes are obligate invertebrate parasites dating back to the Early Cretaceous. Their fossil record is sparse, especially before the Cenozoic, thus little is known about their early host ...associations. This study reports 16 new mermithids associated with their insect hosts from mid-Cretaceous Kachin amber, 12 of which include previously unknown hosts. These fossils indicate that mermithid parasitism of invertebrates was already widespread and played an important role in the mid-Cretaceous terrestrial ecosystem. Remarkably, three hosts (bristletails, barklice, and perforissid planthoppers) were previously unknown to be parasitized by mermithids both past and present. Furthermore, our study shows that in contrast to their Cenozoic counterparts, Cretaceous nematodes including mermithids are more abundant in non-holometabolous insects. This result suggests that nematodes had not completely exploited the dominant Holometabola as their hosts until the Cenozoic. This study reveals what appears to be a vanished history of nematodes that parasitized Cretaceous insects.
The fossil record of ambrosia beetles is summarized and a new genus and species in the subfamily Mecopelminae, Gongyloceria dominicana gen. et sp. nov. is described. The new genus differs from the ...extant genus Mecopelmus Blackman, 1944, possessing weakly elongated tarsi, finely faceted eyes, a scape not reaching the posterior margin of the eye, coarsely sculptured pronotum and elytra, and a larger body size. It is the first Miocene record of the Mecopelminae. The genus Xyleborites Wickham, 1913, placem. n. is transferred from the Scolytidae to the Platypodidae. A list of the fossil Platypodidae, including a key to the subfamilies and tribes of ambrosia beetles, is presented. Xyleborites longipennis Wickham, 1913 and Gongyloceria dominicana sp. nov. may have been related to Paullinieae recorded from the late Eocene and the early Miocene of North and Central America. Distribution maps with fossil records for ambrosia beetles are included.
The Myanmar amber fossil Endobeuthos paleosum was originally described as composed of an individual flower with a calyx of numerous, helically arranged sepals, a whorl of petals, and 60+ stamens each ...bearing a single bisporangiate anther. The 6 flowers, embedded together in a single block of amber, were described as varying in their calyx pubescence and length of corolla segments. The numerous stamens, with their single anther, led to a hypothesized relationship with certain members of family Dilleniaceae. We now propose a complete reinterpretation of this fossil as being an involucrate capitulum of family Proteaceae, in which the numerous “stamens” are identified instead as staminate flowers, although of reduced and highly modified morphology. Organs previously called the calyx and corolla are instead a series of helically-arranged bracts that surround the tight cluster of flowers. The Proteaceae being a diverse and significant element in Southern Hemisphere floras, the reinterpretation of Endobeuthos is important in providing the first Cretaceous fossil flower identified for the family, dated at some 20 my younger than the proposed Proteaceae crown group age of 119 Mya.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
BACKGROUND: Both sexes of bat flies in the families Nycteribiidae and Streblidae (Diptera: Hippoboscoidea) reside in the hair or on the wing membranes of bats and feed on blood. Members of the ...Nycteribiidae transmit bat malaria globally however extant streblids have never been implemented as vectors of bat malaria. The present study shows that during the Tertiary, streblids also were vectors of bat malaria. RESULTS: A new haemospororidan, Vetufebrus ovatus, n. gen., n. sp., (Haemospororida: Plasmodiidae) is described from two oocysts attached to the midgut wall and sporozoites in salivary glands and ducts of a fossil bat fly (Diptera: Streblidae) in Dominican amber. The new genus is characterized by ovoid oocysts, short, stubby sporozoites with rounded ends and its occurrence in a fossil streblid. This is the first haemosporidian reported from a streblid bat fly and shows that representatives of the Hippoboscoidea were vectoring bat malaria in the New World by the mid-Tertiary. CONCLUSIONS: This report is the first evidence of an extant or extinct streblid bat fly transmitting malaria. Discovering a mid-tertiary malarial parasite in a fossil streblid that closely resembles members of a malarial genus found in nycteribiid bat flies today shows how little we know about the vector associations of streblids. While no malaria parasites have been found in extant streblids, they probably occur and it is possible that streblids were the earliest lineage of flies that transmitted bat malaria to Chiroptera.
The recently described fossil angiosperm genus Eophylica (Rhamnaceae) was based on 18 amber-embedded specimens derived from two sites in northern Myanmar. A vegetatively similar fossil, which came ...from the same amber mines but which lacked flowers, had been previously described as a putative green alga and given the name Electrophycus. The dimensions and vegetative aspect of that taxon’s holotype specimen are identical with those of the Eophylica fossils. Four additional specimens were acquired by the senior author after the publication of Electrophycus, all of which have a single terminal flower that is either immature or essentially fully formed. Using techniques of floral dissection, high magnification microscopy, and microphotography of the better-developed flowers, we present a more detailed picture of the floral organs, especially the stamens and style, of Eophylica. These flowers differ from the holotype specimen of Eophylica and 3 of its paratypes in that they possess involucral bracts of a so-called ‘pseudanthial head,’ a structure that the authors of Eophylica had only ascribed to certain other paratype specimens of the genus.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NMLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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