Skip header and navigation

Refine By

6 records – page 1 of 1.

Bird evolution in the Eocene: climate change in Europe and a Danish fossil fauna.

https://arctichealth.org/en/permalink/ahliterature81183
Source
Biol Rev Camb Philos Soc. 2006 Nov;81(4):483-99
Publication Type
Article
Date
Nov-2006
Author
Lindow Bent E K
Dyke Gareth J
Author Affiliation
School of Biology and Environmental Science, University College Dublin, Belfield, Dublin 4, Ireland.
Source
Biol Rev Camb Philos Soc. 2006 Nov;81(4):483-99
Date
Nov-2006
Language
English
Publication Type
Article
Keywords
Animals
Biodiversity
Birds - anatomy & histology - classification
Climate
Denmark
Europe
Evolution
Female
Fossils
Male
Paleontology
Phylogeny
Abstract
The pattern of the evolutionary radiation of modern birds (Neornithes) has been debated for more than 10 years. However, the early fossil record of birds from the Paleogene, in particular, the Lower Eocene, has only recently begun to be used in a phylogenetic context to address the dynamics of this major vertebrate radiation. The Cretaceous-Paleogene (K-P) extinction event dominates our understanding of early modern bird evolution, but climate change throughout the Eocene is known to have also played a major role. The Paleocene and Lower Eocene was a time of avian diversification as a result of favourable global climatic conditions. Deteriorations in climate beginning in the Middle Eocene appear to be responsible for the demise of previously widespread avian lineages like Lithornithiformes and Gastornithidae. Other groups, such as Galliformes display replacement of some lineages by others, probably related to adaptations to a drier climate. Finally, the combination of slowly deteriorating climatic conditions from the Middle Eocene onwards, appears to have slowed the evolutionary rate in Europe, as avian faunas did not differentiate markedly until the Oligocene. Taking biotic factors in tandem with the known Paleogene fossil record of Neornithes has recently begun to illuminate this evolutionary event. Well-preserved fossil taxa are required in combination with ever-improving phylogenetic hypotheses for the inter-relationships of modern birds founded on morphological characters. One key avifauna of this age, synthesised for the first time herein, is the Lower Eocene Fur Formation of Denmark. The Fur birds represent some of the best preserved (often in three dimensions and with soft tissues) known fossil records for major clades of modern birds. Clear phylogenetic assessment of these fossils will prove critical for future calibration of the neornithine evolutionary timescale. Some early diverging clades were clearly present in the Paleocene as evidenced directly by new fossil material alongside the phylogenetically constrained Lower Eocene taxa. A later Oligocene radiation of clades other than Passeriformes is not supported by available fossil data.
PubMed ID
16893476 View in PubMed
Less detail

Carotenoids, sexual signals and immune function in barn swallows from Chernobyl.

https://arctichealth.org/en/permalink/ahliterature72344
Source
Proc Biol Sci. 1999 Jun 7;266(1424):1111-6
Publication Type
Article
Date
Jun-7-1999
Author
A. Camplani
N. Saino
A P Møller
Author Affiliation
Dipartmento di Biologia, Università di Milano, Italy.
Source
Proc Biol Sci. 1999 Jun 7;266(1424):1111-6
Date
Jun-7-1999
Language
English
Publication Type
Article
Keywords
Accidents, Radiation
Animals
Birds - anatomy & histology - immunology - parasitology
Carotenoids
Color
Ectoparasitic Infestations - veterinary
Feathers
Female
Male
Power Plants
Radiation Effects
Research Support, Non-U.S. Gov't
Sex Behavior, Animal
Sex Characteristics
Ukraine
Abstract
Carotenoids have been hypothesized to facilitate immune function and act as free-radical scavengers, thereby minimizing the frequency of mutations. Populations of animals exposed to higher levels of free radicals are thus expected to demonstrate reduced sexual coloration if use of carotenoids for free-radical scavenging is traded against use for sexual signals. The intensity of carotenoid-based sexual coloration was compared among three populations of barn swallows Hirundo rustica differing in exposure to radioactive contamination. Lymphocyte and immunoglobulin concentrations were depressed, whereas the heterophil:lymphocyte ratio, an index of stress, was enhanced in Chernobyl swallows compared to controls. Spleen size was reduced in Chernobyl compared to that of two control populations. Sexual coloration varied significantly among populations, with the size of a secondary sexual character (the length of the outermost tail feathers) being positively related to coloration in the two control populations, but not in the Chernobyl population. Thus the positive covariation between coloration and sexual signalling disappeared in the population subject to intense radioactive contamination. These findings suggest that the reliable signalling function of secondary sexual characters breaks down under extreme environmental conditions, no longer providing reliable information about the health status of males.
PubMed ID
10406129 View in PubMed
Less detail

Commonness and ecology, but not bigger brains, predict urban living in birds.

https://arctichealth.org/en/permalink/ahliterature267911
Source
BMC Ecol. 2015;15:12
Publication Type
Article
Date
2015
Author
Svein Dale
Jan T Lifjeld
Melissah Rowe
Source
BMC Ecol. 2015;15:12
Date
2015
Language
English
Publication Type
Article
Keywords
Adaptation, Physiological
Agriculture
Animals
Birds - anatomy & histology
Brain - anatomy & histology
Cities
Ecosystem
Forests
Models, Biological
Norway
Organ Size
Phylogeny
Population Density
Population Dynamics
Regression Analysis
Urbanization
Abstract
Several life history and ecological variables have been reported to affect the likelihood of species becoming urbanized. Recently, studies have also focused on the role of brain size in explaining ability to adapt to urban environments. In contrast, however, little is known about the effect of colonization pressure from surrounding areas, which may confound conclusions about what makes a species urban. We recorded presence/absence data for birds in 93 urban sites in Oslo (Norway) and compared these with species lists generated from 137 forest and 51 farmland sites surrounding Oslo which may represent source populations for colonization.
We found that the frequency (proportion of sites where present) of a species within the city was strongly and positively associated with its frequency in sites surrounding the city, as were both species breeding habitat and nest site location. In contrast, there were generally no significant effects of relative brain mass or migration on urban occupancy. Furthermore, analyses of previously published data showed that urban density of birds in six other European cities was also positively and significantly associated with density in areas outside cities, whereas relative brain mass showed no such relationship.
These results suggest that urban bird communities are primarily determined by how frequently species occurred in the surrounding landscapes and by features of ecology (i.e. breeding habitat and nest site location), whereas species' relative brain mass had no significant effects.
Notes
Cites: Biol Rev Camb Philos Soc. 2010 Aug;85(3):643-6720128785
Cites: Proc Natl Acad Sci U S A. 2011 Mar 29;108(13):5325-3021402912
Cites: PLoS One. 2011;6(4):e1885921526193
Cites: Biol Lett. 2011 Oct 23;7(5):730-221525053
Cites: Mol Biol Evol. 2012 Aug;29(8):1969-7322367748
Cites: Oecologia. 2012 Nov;170(3):867-7522588633
Cites: Nature. 2012 Nov 15;491(7424):444-823123857
Cites: Proc Biol Sci. 2013 Feb 22;280(1753):2012261623282997
Cites: Evolution. 2013 Oct;67(10):3052-6024094354
Cites: Ecol Lett. 2014 Aug;17(8):942-5024835452
Cites: BMC Ecol. 2015;15:1225888385
Cites: J Anim Ecol. 2015 Jan;84(1):79-8924910268
Cites: Proc Biol Sci. 2002 May 7;269(1494):961-712028780
Cites: J Appl Physiol (1985). 1995 Sep;79(3):1027-318567498
Cites: J Evol Biol. 2005 Jan;18(1):223-3715669979
Cites: Proc Natl Acad Sci U S A. 2005 Apr 12;102(15):5460-515784743
Cites: Proc Biol Sci. 2005 Nov 7;272(1578):2305-1116191644
Cites: Trends Ecol Evol. 2006 Apr;21(4):186-9116701084
Cites: Proc Biol Sci. 2007 Feb 22;274(1609):453-6417476764
Cites: Ecol Appl. 2007 Jan;17(1):168-8017479843
Cites: Biol Rev Camb Philos Soc. 2007 Nov;82(4):591-60517944619
Cites: Biol Lett. 2007 Dec 22;3(6):670-317766238
Cites: Oecologia. 2009 Apr;159(4):849-5819139922
Cites: Proc Biol Sci. 2009 Jul 7;276(1666):2403-1019364751
Cites: PLoS One. 2010;5(3):e961720224776
PubMed ID
25888385 View in PubMed
Less detail

A Large Ornithurine Bird (Tingmiatornis arctica) from the Turonian High Arctic: Climatic and Evolutionary Implications.

https://arctichealth.org/en/permalink/ahliterature292404
Source
Sci Rep. 2016 12 19; 6:38876
Publication Type
Journal Article
Research Support, U.S. Gov't, Non-P.H.S.
Date
12-19-2016
Author
Richard K Bono
Julia Clarke
John A Tarduno
Donald Brinkman
Author Affiliation
Department of Earth &Environmental Sciences, University of Rochester, Rochester, New York, 14627, USA.
Source
Sci Rep. 2016 12 19; 6:38876
Date
12-19-2016
Language
English
Publication Type
Journal Article
Research Support, U.S. Gov't, Non-P.H.S.
Keywords
Animals
Arctic Regions
Biological Evolution
Birds - anatomy & histology - physiology
Canada
Fossils
Tropical Climate
Abstract
Bird fossils from Turonian (ca. 90?Ma) sediments of Axel Heiberg Island (High Canadian Arctic) are among the earliest North American records. The morphology of a large well-preserved humerus supports identification of a new volant, possibly diving, ornithurine species (Tingmiatornis arctica). The new bird fossils are part of a freshwater vertebrate fossil assemblage that documents a period of extreme climatic warmth without seasonal ice, with minimum mean annual temperatures of 14?°C. The extreme warmth allowed species expansion and establishment of an ecosystem more easily able to support large birds, especially in fresh water bodies such as those present in the Turonian High Arctic. Review of the high latitude distribution of Northern Hemisphere Mesozoic birds shows only ornithurine birds are known to have occupied these regions. We propose physiological differences in ornithurines such as growth rate may explain their latitudinal distribution especially as temperatures decline later in the Cretaceous. Distribution and physiology merit consideration as factors in their preferential survival of parts of one ornithurine lineage, Aves, through the K/Pg boundary.
Notes
Cites: Proc Natl Acad Sci U S A. 2002 Oct 29;99(22):14020-5 PMID 12388778
Cites: Proc Natl Acad Sci U S A. 2011 Sep 13;108(37):15253-7 PMID 21914849
Cites: Nature. 2005 Jan 20;433(7023):305-8 PMID 15662422
Cites: Naturwissenschaften. 2010 Jul;97(7):673-82 PMID 20532472
Cites: Science. 1998 Dec 18;282(5397):2241-4 PMID 9856943
Cites: Science. 2006 Jun 16;312(5780):1640-3 PMID 16778053
Cites: Ecology. 2007 Nov;88(11):2915-25 PMID 18051660
Cites: Proc Biol Sci. 2008 Dec 7;275(1652):2675-85 PMID 18713718
PubMed ID
27991515 View in PubMed
Less detail

Multiphotoreceptor and multioscillator system in avian circadian organization.

https://arctichealth.org/en/permalink/ahliterature5377
Source
Microsc Res Tech. 2001 Apr 1;53(1):43-7
Publication Type
Article
Date
Apr-1-2001
Author
T. Oishi
M. Yamao
C. Kondo
Y. Haida
A. Masuda
S. Tamotsu
Author Affiliation
Graduate School of Human Culture, Nara Women's University, Nara 630-8506, Japan. oishi@cc.nara-wu.ac.jp
Source
Microsc Res Tech. 2001 Apr 1;53(1):43-7
Date
Apr-1-2001
Language
English
Publication Type
Article
Keywords
Animals
Biological Clocks - physiology
Birds - anatomy & histology - physiology
Circadian Rhythm - physiology
Hypothalamus - cytology - physiology
Ocular Physiology
Photoperiod
Photoreceptors, Vertebrate - physiology
Pineal Gland - physiology - ultrastructure
Abstract
Photoperiodism and circadian rhythms have been studied intensively in birds because Aves are typical seasonal breeders and diurnal animals. Light is the most important environmental factor involved in entrainment of circadian rhythms and photoperiodism. The eyes and the extraocular photoreceptors, such as the pineal organ and hypothalamus, are reported to have an important function not only for photoreception but also for circadian organization in nonmammalian vertebrates, including birds. In this report, we review the roles of the eyes, pineal organ, and deep brain as the components of the multiphotoreceptor and multioscillator system in avian circadian organization.
PubMed ID
11279669 View in PubMed
Less detail

A reappraisal of Cerebavis cenomanica (Aves, Ornithurae), from Melovatka, Russia.

https://arctichealth.org/en/permalink/ahliterature282183
Source
J Anat. 2016 08;229(2):215-27
Publication Type
Article
Date
08-2016
Author
Stig A Walsh
Angela C Milner
Estelle Bourdon
Source
J Anat. 2016 08;229(2):215-27
Date
08-2016
Language
English
Publication Type
Article
Keywords
Animals
Biological Evolution
Birds - anatomy & histology
Brain - anatomy & histology
Fossils
Phylogeny
Russia
Skull - anatomy & histology
Abstract
The evolution of the avian brain is of crucial importance to studies of the transition from non-avian dinosaurs to modern birds, but very few avian fossils provide information on brain morphological development during the Mesozoic. An isolated specimen from the Cenomanian of Melovatka in Russia was described by Kurochkin and others as a fossilized brain, designated the holotype of Cerebavis cenomanica Kurochkin and Saveliev and tentatively referred to Enantiornithes. We have previously highlighted that this specimen is an incomplete skull, rendering the diagnostic characters invalid and Cerebavis cenomanica a nomen dubium. We provide here a revised diagnosis of Cerebavis cenomanica based on osteological characters, and a reconstruction of the endocranial morphology (= brain shape) based on µCT investigation of the braincase. Absence of temporal fenestrae indicates an ornithurine affinity for Cerebavis. The brain of this taxon was clearly closer to that of modern birds than to Archaeopteryx and does not represent a divergent evolutionary pathway as originally concluded by Kurochkin and others. No telencephalic wulst is present, suggesting that this advanced avian neurological feature was not recognizably developed 93 million years ago.
PubMed ID
26553244 View in PubMed
Less detail

6 records – page 1 of 1.