Journal Article•
Precipitation and large herbivorous mammals II: application to fossil data
TL;DR: The early Miocene retained the overall humid conditions of the late Paleogene, while the late Miocene as a whole was a time of large changes, and there was continent-wide restructuring of the distribution of environments.
Abstract: Background: We developed a method to estimate precipitation using mammalian ecomorphology, specifically the relative height of the molars of herbivores (see companion paper, this issue) Question: If we apply the new method to paleoenvironments, do the results agree with previous results from fossil mammals and paleobotanical proxies? Data: Large herbivorous fossil mammals of Eurasia Data from NOW database covers 23–22 Ma and is Eurasia-wide Method: We apply the new precipitation estimation method (based on present-day mammalian ecomorphology) to fossil assemblages from different localities Conclusions: The early Miocene retained the overall humid conditions of the late Paleogene A shift to more arid conditions began during the middle Miocene The late Miocene as a whole was a time of large changes, and there was continent-wide restructuring of the distribution of environments Our new results agree with previous investigations and the mammal proxy data are in good agreement with palaeovegetation data Mammals and vegetation produce similar precipitation values and large-scale patterns
Citations
More filters
TL;DR: The evolution and subsequent ecological expansion of grasses (Poaceae) since the Late Cretaceous have resulted in the establishment of one of Earth's dominant biomes, the temperate and tropical grasslands, at the expense of forests as mentioned in this paper.
Abstract: The evolution and subsequent ecological expansion of grasses (Poaceae) since the Late Cretaceous have resulted in the establishment of one of Earth’s dominant biomes, the temperate and tropical grasslands, at the expense of forests. In the past decades, several new approaches have been applied to the fossil record of grasses to elucidate the patterns and processes of this ecosystem transformation. The data indicate that the development of grassland ecosystems on most continents was a multistage process involving the Paleogene appearance of (C3 and C4) open-habitat grasses, the mid-late Cenozoic spread of C3 grass-dominated habitats, and, finally, the Late Neogene expansion of C4 grasses at tropical-subtropical latitudes. The evolution of herbivores adapted to grasslands did not necessarily coincide with the spread of open-habitat grasses. In addition, the timing of these evolutionary and ecological events varied between regions. Consequently, region-by-region investigations using both direct (plant fossils) and indirect (e.g., stable carbon isotopes, faunas) evidence are required for a full understanding of the tempo and mode of grass and grassland evolution.
549 citations
TL;DR: The results indicate that the evolutionary history of cetartiodactyls was punctuated by four main phases of rapid radiation during the Cenozoic era, and shows that the high species diversity now observed in the families Bovidae and Cervidae accumulated mainly during the Late Miocene and Plio-Pleistocene.
472 citations
TL;DR: In this paper, the authors examined the evolution of Miocene climate (both moisture and temperature) within five separate regions of Eurasia to help understand the large scale controls of long-term moisture in Central Asia.
317 citations
TL;DR: Hypsodonty among ungulates has, over the past 150 years, formed the basis of widespread palaeoecological interpretations, and has figured prominently in the evolutionary study of the spread of grasslands in the mid Cenozoic.
Abstract: High-crowned (hypsodont) teeth are widely found among both extant and extinct mammalian herbivores. Extant grazing ungulates (hoofed mammals) have hypsodont teeth (a derived condition), and so extinct hypsodont forms have usually been presumed to have been grazers. Thus, hypsodonty among ungulates has, over the past 150 years, formed the basis of widespread palaeoecological interpretations, and has figured prominently in the evolutionary study of the spread of grasslands in the mid Cenozoic. However, perceived inconsistencies between levels of hypsodonty and dental wear patterns in both extant and extinct ungulates have caused some workers to reject hypsodonty as a useful predictive tool in palaeobiology, a view that we consider both misguided and premature. Despite the acknowledged association between grazing and hypsodonty, the quantitative relationship of hypsodonty to the known ecology of living ungulate species, critical in making interpretations of the fossil record, was little studied until the past two decades. Also, much of the literature on ungulate ecology relevant to understanding hypsodonty has yet to be fully incorporated into the perspectives of palaeontologists. Here we review the history and current state of our knowledge of the relationship between hypsodonty and ungulate ecology, and reassert the value of hypsodonty for our understanding of ungulate feeding behaviour. We also show how soil consumption, rather than the consumption of grass plants per se, may be the missing piece of the puzzle in understanding the observed correlation between diets, habitats, and hypsodonty in ungulates. Additionally, we show how hypsodonty may impact life-history strategies, and resolve some controversies regarding the relevance of hypsodonty to the prediction of the diets of extinct species. This in turn strengthens the utility of hypsodonty in the determination of past environmental conditions, and we provide a revised view of a traditional example of evolutionary trends in palaeobiology, that of the evolution of hypsodonty in horses and its correlation with the Miocene spread of grasslands in North America.
297 citations
Cites background from "Precipitation and large herbivorous..."
...Explanations for the evolution of hypsodonty that propose that its primary adaptive value is the broadening of the feeding niche (e.g. Feranec, 2003, 2007; Rivals et al., 2010) seem to make sense only if one expects hypsodonty to be generally increasing over time, rather than with the actuality…...
[...]
TL;DR: While the MS indicates predominantly the wear effect of the diet, HI represents an adaptation to a wear effect that comprises both diet and environment (external abrasives) that must reduce tooth height without causing macroscopic changes in tooth facet development.
Abstract: 1. The evolution of high-crowned teeth or hypsodonty in herbivorous mammals is widely interpreted as a species-specific adaptation to increasingly wear-inducing diets and environments at evolutionary time scales, with internal abrasives (such as phytoliths in grasses) and/or external abrasives (such as dust or grit) as putative causative factors. The mesowear score (MS) instead describes tooth wear experienced by individual animals during their lifetime.
2. Under the assumption that the abrasiveness that causes the MS in individuals is the same abrasiveness to which species adapted by evolving hypsodonty, one would expect a close correlation between the MS and the hypsodonty index (HI). Alternatively, if these two measures reflect different aspects of wear, one would expect differences in the way that proxies of diet or environment/climate correlate with each parameter.
3. In order to test these hypotheses, we collated a dataset on the HI, MS, percentage of grass in the natural diet (%grass), habitat (open, intermediate, closed) and annual precipitation (PREC) in extant mammalian herbivores. The availability of a quantitative MS constrained the dataset to 75 species. Data were analysed with and without phylogenetic generalized least squares (PGLS).
4. Correlations with PREC were stronger for HI than for MS, whereas correlations with %grass were similar for HI and MS. Habitat had a significant influence on the relationship with %grass for HI but not for MS. Habitat also had a significant influence on the relationship between HI and MS. MS improved the predictive power of HI for %grass, but not for PREC.
5. These results suggest that while the MS indicates predominantly the wear effect of the diet (internal abrasives), HI represents an adaptation to a wear effect that comprises both diet and environment (external abrasives). The additional environmental wear effect must reduce tooth height without causing macroscopic changes in tooth facet development as described by the MS.
6. The most parsimonious explanation for the apparent discrepancy between HI and MS is that external abrasives of very fine particle size play a major role in naturally occurring tooth wear. The experimental testing of this hypothesis will enhance our understanding of the processes involved in tooth wear.
143 citations
Cites background from "Precipitation and large herbivorous..."
...…2008), with proxies that indicate diet quality and possibly low or tall grass feeding (Codron et al. 2007, 2008), with the openness of the habitat (Mendoza & Palmqvist 2008) and with annual precipitation (Damuth & Fortelius 2001, Damuth et al. 2002, Fortelius et al. 2002, Eronen et al. 2010a, b)....
[...]
References
More filters
TL;DR: The data support the concept that changes in atmospheric CO2 concentrations, although linked to climate changes, were not the major driving force of Cenozoic cooling.
Abstract: Continental climate evolution of Central Europe has been reconstructed quantitatively for the last 45 million years providing inferred data on mean annual temperature and precipitation, and winter and summer temperatures. Although some regional effects occur, the European Cenozoic continental climate record correlates well with the global oxygen isotope record from marine environments. During the last 45 million years, continental cooling is especially pronounced for inferred winter temperatures but hardly observable from summer temperatures. Correspondingly, Cenozoic cooling in Central Europe is directly associated with an increase of seasonality. In contrast, inferred Cenozoic mean annual precipitation remained relatively stable, indicating the importance of latent heat transport throughout the Cenozoic. Moreover, our data support the concept that changes in atmospheric CO2 concentrations, although linked to climate changes, were not the major driving force of Cenozoic cooling.
598 citations
"Precipitation and large herbivorous..." refers background or result in this paper
...Mosbrugger et al. (2005) conclude that the increase of seasonality in Europe during the late Miocene was due mostly to lower winter temperatures....
[...]
...According to paleobotanical proxies, the early Miocene was a time of weak seasonality and shallow temperature gradients (Utescher et al., 2000; Mosbrugger et al., 2005; Bruch et al., 2007), which is in line with our estimates presented here....
[...]
...According to Utescher et al. (2000) and Mosbrugger et al. (2005), based on paleobotanical evidence, the mean annual precipitation in central Europe was at a constant level of 1250 mm until the late Pliocene (Zanclean)....
[...]
...The results obtained here are also comparable to those obtained in other studies, including vegetation-based reconstructions of paleoenvironmental conditions (Utescher et al., 2000; Ivanov et al., 2002; Bruch et al., 2004, 2007; Mosbrugger et al., 2005)....
[...]
TL;DR: Functional demands, with a note on dental wear, are presented.
Abstract: ( I ) Types of solutions available . . . . . . . . . (2) Increased wear resistance of dental tissues . . . . . . (3) Increased tooth size . . . . . . . . . . . (4) Additional teeth, and a discussion of bilophodonty . . , . , (5) Increased tooth height . . . . . . . . . . (6) Combinations of methods . . . . . . . . . . IV. Conclusion . . . . . . . . . . . . . V. Acknowledgements. . . . . . . . . . . . VI. References . . . . . . . . . . . . . (2) Functional demands, with a note on dental wear
385 citations
"Precipitation and large herbivorous..." refers background in this paper
...But eating other plants in more arid areas may entail consuming a good deal of abrasive dust and grit (see Janis and Fortelius, 1988)....
[...]
Book•
01 Sep 1974
TL;DR: In this article, the evolution of vertebrate life has been studied in the context of oceanic and coral reef regions in the South-east of the United States, and the effects of different modes of elevritioiis on evolution of terrestrial life have been discussed.
Abstract: CONTENTS Page 1 liesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172 I ntroductlon .......................................................... 173 Alternations of elevritiwi tiirtl vlluttltt . d u r h l ~ gealoglcal time ......... 173 I'ermnneucy of tlir OWIIII linsliis ................................... 171 Dlstrlbiitloii of ltliitl iind water. present riiitl pnst . . . . . . . . . . . . . . . . . . . 175 Effects of nlternritioiis of elcvntloii tiiid clltunte upon evolution of terrestrial fnunns ............................................... 176 Comparison wlth tlir puIeoiit.olo;icuI rcconl ........................ 178 Interpretntlon of supposed exc.eptlons . . . . . . . . . . . . . Prlnclples of tllspersiil ........................... Heview of the evolution of vertehrate life .......................... 181 Imperfectloit of the geologlcril record .................................. 183 ZOaloglcal regions. pnst nud present ................................... 185 Former bnrrlers rind brltlgw . . . . . . . . . . . . . . . . . . . . . . . 189 Heglonnl correlntlon ................................................... 191 Synchronism nnd homotaxls ....................................... 192 Terttnry currelntion I n South .\tuerlc.ti. . . Centers of disperwil ......................... Oceanic and contlnenhl Islands . . . . . . . . . . . . . . . .
328 citations
"Precipitation and large herbivorous..." refers methods in this paper
...Mammals have been used to describe and reconstruct paleoenvironments for at least a century (e.g. Matthew, 1915)....
[...]
Journal Article•
TL;DR: Fossil teeth of terrestrial plant-eating mammals offer a new, quasi-quantitative proxy for environmental aridity that resolves previously unseen regional features across the Eurasian continent from 24 to 2 million years ago.
Abstract: Fossil teeth of terrestrial plant-eating mammals offer a new, quasi-quantitative proxy for environmental aridity that resolves previously unseen regional features across the Eurasian continent from 24 to 2 million years ago. The pattern seen prior to 11 million years ago are quite different from today’s. Thereafter, a progressively modern rainfall distribution developed at about 7 to 5 million years ago when East Asia remained unexpectedly humid while Europe experienced a transient phase of strong aridity. Mean hypsodonty is a geographically extensive and stratigraphically well-resolved palaeoprecipitation proxy that can be used to constrain the regional details of vegetation and climate models.
324 citations
"Precipitation and large herbivorous..." refers background or methods or result in this paper
...1A, based on the method of Fortelius et al. (2002)] and our new precipitation estimates [Fig....
[...]
...The new precipitation estimation method confirms the results of previous investigations (e.g. Fortelius et al., 2002, 2003, 2006)....
[...]
...Damuth and Fortelius (2001) introduced and Fortelius et al. (2002) applied the use of mean hypsodonty to estimate past precipitation values from fossil molar teeth of large herbivorous mammals....
[...]
...A simple regression using PMH explains over 60% of the variance in mean annual precipitation for modern mammal communities (Damuth et al., 2002), and in this regard is an extension of the method of Fortelius et al. (2002) when applied to well-sampled, individual fossil localities....
[...]
...In this paper, our objective is to compare the published results of the method of Fortelius et al. (2002) with those of this new method (Eronen et al., 2010), both having been applied to a set of fossil localities covering the same time-span and geographical extent....
[...]
TL;DR: In this article, a robust, comprehensive global biome reconstruction for the Middle Pliocene (c. 3.6-2.6 Ma) is presented, which is based on an internally consistent palaeobotanical data set and a coupled climate-vegetation model.
Abstract: Aim
To produce a robust, comprehensive global biome reconstruction for the Middle Pliocene (c. 3.6–2.6 Ma), which is based on an internally consistent palaeobotanical data set and a state-of-the-art coupled climate–vegetation model. The reconstruction gives a more rigorous picture of climate and environmental change during the Middle Pliocene and provides a new boundary condition for future general circulation model (GCM) studies. Location Global.
Methods
Compilation of Middle Pliocene vegetation data from 202 marine and terrestrial sites into the comprehensive GIS data base TEVIS (Tertiary Environmental Information System). Translation into an internally consistent classification scheme using 28 biomes. Comparison and synthesis of vegetation reconstruction from palaeodata with the outputs of the mechanistically based BIOME4 model forced by climatology derived from the HadAM3 GCM.
Results
The model results compare favourably with available palaeodata and highlight the importance of employing vegetation–climate feedbacks and the anomaly method in biome models. Both the vegetation reconstruction from palaeobotanical data and the BIOME4 prediction indicate a general warmer and moister climate for the Middle Pliocene. Evergreen taiga as well as temperate forest and grassland shifted northward, resulting in much reduced tundra vegetation. Warm-temperate forests (with subtropical taxa) spread in mid and eastern Europe and tropical savannas and woodland expanded in Africa and Australia at the expense of deserts. Discrepancies which occurred between data reconstruction and model simulation can be related to: (1) poor spatial model resolution and data coverage; (2) uncertainties in delimiting biomes using climate parameters; or (3) uncertainties in model physics and/or geological boundary conditions.
Main conclusions
The new global biome reconstruction combines vegetation reconstruction from palaeobotanical proxies with model simulations. It is an important contribution to the further understanding of climate and vegetation changes during the Middle Pliocene warm interval and will enhance our knowledge about how vegetation may change in the future.
270 citations
"Precipitation and large herbivorous..." refers methods in this paper
...Our methods seem to represent middle Pliocene conditions better, although we do not see the warm and humid conditions as clearly as the literature suggests we should (Salzmann et al., 2008)....
[...]