scholarly journals Rise of the titans: baleen whales became giants earlier than thought

2019 ◽  
Vol 15 (5) ◽  
pp. 20190175 ◽  
Author(s):  
Giovanni Bianucci ◽  
Felix G. Marx ◽  
Alberto Collareta ◽  
Agata Di Stefano ◽  
Walter Landini ◽  
...  
Keyword(s):  
Feeding Strategy ◽  
Early Pleistocene ◽  
Additional Material ◽  
Baleen Whales ◽  
Mode Shift ◽  
Extant Species ◽  
Size Evolution ◽  
Body Size Evolution ◽  
Long Term Impact

Baleen whales (Mysticeti) are major ecosystem engineers, thanks to their enormous size and bulk filter feeding strategy. Their signature gigantism is thought to be a relatively recent phenomenon, resulting from a Plio-Pleistocene mode shift in their body size evolution. Here, we report the largest whale fossil ever described: an Early Pleistocene (1.5–1.25 Ma) blue whale from Italy with an estimated body length of up to 26 m. Macroevolutionary modelling taking into account this specimen, as well as additional material from the Miocene of Peru, reveals that the proposed mode shift occurred either somewhat earlier, or perhaps not at all. Large-sized mysticetes comparable to most extant species have existed since at least the Late Miocene, suggesting a long-term impact on global marine ecosystems.

Evolution of body mass in the Pan-Alcidae (Aves, Charadriiformes): the effects of combining neontological and paleontological data

Paleobiology ◽  
2015 ◽  
Vol 42 (1) ◽  
pp. 8-26 ◽  
Author(s):  
N. Adam Smith
Keyword(s):  
Body Mass ◽  
Mass Range ◽  
Extinct Species ◽  
Paleontological Data ◽  
Ideal Candidate ◽  
Extant Species ◽  
Size Evolution ◽  
Body Size Evolution ◽  
Phylogenetic Hypotheses ◽  
Maximum Body

AbstractHypotheses regarding the evolution of many clades are often generated in the absence of data from the fossil record and potential biases introduced by exclusion of paleontological data are frequently ignored. With regard to body size evolution, extinct taxa are frequently excluded because of the lack of body mass estimates—making identification of reliable clade specific body mass estimators crucial to evaluating trends on paleontological timescales. Herein, I identify optimal osteological dimensions for estimating body mass in extinct species of Pan-Alcidae (Aves, Charadriiformes) and utilize newly generated estimates of body mass to demonstrate that the combination of neontological and paleontological data produces results that conflict with hypotheses generated when extant species data are analyzed in isolation. The wing-propelled diving Pan-Alcidae are an ideal candidate for comparing estimates of body mass evolution based only on extant taxa with estimates generated including fossils because extinct species diversity (≥31 species) exceeds extant diversity, includes examples from every extant genera, and because phylogenetic hypotheses of pan-alcid relationships are not restricted to the 23 extant species. Phylogenetically contextualized estimation of body mass values for extinct pan-alcids facilitated evaluation of broad scale trends in the evolution of pan-alcid body mass and generated new data bearing on the maximum body mass threshold for aerial flight in wing-propelled divers. The range of body mass in Pan-Alcidae is found to exceed that of all other clades of Charadriiformes (shorebirds and allies) and intraclade body mass variability is recognized as a recurring theme in the evolution of the clade. Finally, comparisons of pan-alcid body mass range with penguins and the extinct †Plotopteridae elucidate potentially shared constraints among phylogenetically disparate yet ecologically similar clades of wing-propelled divers.

scholarly journals Accelerated body size evolution during cold climatic periods in the Cenozoic

2017 ◽  
Vol 114 (16) ◽  
pp. 4183-4188 ◽  
Author(s):  
Julien Clavel ◽  
Hélène Morlon
Keyword(s):  
Body Size ◽  
Biotic Interactions ◽  
Morphological Diversity ◽  
Evolutionary Rates ◽  
Phenotypic Evolution ◽  
Geological Time ◽  
Radiation Theory ◽  
Extant Species ◽  
Size Evolution ◽  
Body Size Evolution

How ecological and morphological diversity accumulates over geological time is much debated. Adaptive radiation theory has been successful in testing the effects of biotic interactions on the rapid divergence of phenotypes within a clade, but this theory ignores abiotic effects. The role of abiotic drivers on the tempo of phenotypic evolution has been tested only in a few lineages or small clades from the fossil record. Here, we develop a phylogenetic comparative framework for testing if and how clade-wide rates of phenotypic evolution vary with abiotic drivers. We apply this approach to comprehensive bird and mammal phylogenies, body size data for 9,465 extant species, and global average temperature trends over the Cenozoic. Across birds and mammals, we find that the rate of body size evolution is primarily driven by past climate. Unexpectedly, evolutionary rates are inferred to be higher during periods of cold rather than warm climates in most groups, suggesting that temperature influences evolutionary rates by modifying selective pressures rather than through its effect on energy availability and metabolism. The effect of climate on the rate of body size evolution seems to be a general feature of endotherm evolution, regardless of wide differences in species’ ecology and evolutionary history. These results suggest that climatic changes played a major role in shaping species’ evolution in the past and could also play a major role in shaping their evolution in the future.

scholarly journals Adaptive evolution toward larger size in mammals

2015 ◽  
Vol 112 (16) ◽  
pp. 5093-5098 ◽  
Author(s):  
Joanna Baker ◽  
Andrew Meade ◽  
Mark Pagel ◽  
Chris Venditti
Keyword(s):  
Body Size ◽  
Large Body ◽  
Biological Species ◽  
Directional Bias ◽  
Rates Of Evolution ◽  
Extant Species ◽  
Size Evolution ◽  
Mammalian Fossil ◽  
Cope’S Rule

The notion that large body size confers some intrinsic advantage to biological species has been debated for centuries. Using a phylogenetic statistical approach that allows the rate of body size evolution to vary across a phylogeny, we find a long-term directional bias toward increasing size in the mammals. This pattern holds separately in 10 of 11 orders for which sufficient data are available and arises from a tendency for accelerated rates of evolution to produce increases, but not decreases, in size. On a branch-by-branch basis, increases in body size have been more than twice as likely as decreases, yielding what amounts to millions and millions of years of rapid and repeated increases in size away from the small ancestral mammal. These results are the first evidence, to our knowledge, from extant species that are compatible with Cope’s rule: the pattern of body size increase through time observed in the mammalian fossil record. We show that this pattern is unlikely to be explained by several nonadaptive mechanisms for increasing size and most likely represents repeated responses to new selective circumstances. By demonstrating that it is possible to uncover ancient evolutionary trends from a combination of a phylogeny and appropriate statistical models, we illustrate how data from extant species can complement paleontological accounts of evolutionary history, opening up new avenues of investigation for both.

Crisis Phones - Suicide Prevention Versus Suggestion/Contagion Effects

Crisis ◽  
2015 ◽  
Vol 36 (3) ◽  
pp. 220-224 ◽  
Author(s):  
Steven Stack
Keyword(s):  
Suicide Prevention ◽  
Contagion Effects ◽  
Long Term Impact

Abstract. Background: There has been no systematic work on the short- or long-term impact of the installation of crisis phones on suicides from bridges. The present study addresses this issue. Method: Data refer to 219 suicides from 1954 through 2013 on the Skyway Bridge in St. Petersburg, Florida. Six crisis phones with signs were installed in July 1999. Results: In the first decade after installation, the phones were used by 27 suicidal persons and credited with preventing 26 or 2.6 suicides a year. However, the net suicide count increased from 48 in the 13 years before installation of phones to 106 the following 13 years or by 4.5 additional suicides/year (t =3.512, p < .001). Conclusion: Although the phones prevented some suicides, there was a net increase after installation. The findings are interpreted with reference to suggestion/contagion effects including the emergence of a controversial bridge suicide blog.

Long-Term Impact of Participation in the Adolescent Diversion Project

2009 ◽  
Author(s):  
Jenna L. Claes ◽  
Sean S. Hankins ◽  
J. K. Ford
Keyword(s):  
Long Term Impact

966-P: The Long-Term Impact of a Flash Glucose Monitoring System on Glycemic Control

Diabetes ◽  
2019 ◽  
Vol 68 (Supplement 1) ◽  
pp. 966-P
Author(s):  
ATSUSHI FUJIYA ◽  
TOSHIKI KIYOSE ◽  
TAIGA SHIBATA ◽  
HIROSHI SOBAJIMA
Keyword(s):  
Glycemic Control ◽  
Monitoring System ◽  
Glucose Monitoring ◽  
Flash Glucose Monitoring ◽  
Long Term Impact ◽  
Flash Glucose Monitoring System

Dual lumen intervention for aortic dissection: long-term impact on aortic remodeling

2020 ◽  
Vol 27 (1) ◽  
Author(s):  
Xun Yuan ◽  
Andreas Mitsis ◽  
Thomas Semple ◽  
Michael Rubens ◽  
Christoph A. Nienaber
Keyword(s):  
Aortic Dissection ◽  
Long Term Impact ◽  
Aortic Remodeling
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