Modeled physiological mechanisms for observed changes in the late Paleozoic plant fossil record

When one hears the term “ground cover,” one immediately thinks of “grasses.” This perception is so deep-seated that paleobotanists even have been overheard to proclaim that “there was no ground cover before grasses.” Today grasses are so predominant in many environments that this perception is perpetuated easily. On the other hand, it is difficult to imagine the absence or lack of ground cover prior to the mid-Tertiary. We tested the hypothesis that different forms of ground cover existed in the past against examples from the Recent and the fossil record (Table 1). The Recent data were obtained from a large number of sources including those in the ecological, horticultural, and microbiological literature. Other data were derived from our knowledge of Precambrian life, sedimentology and paleosols, and the plant fossil record, especially in situ floras and fossil “monocultures.” Some of the data are original observations, but many others are from the literature. A detailed account of these results will be presented elsewhere (Pfefferkorn and LePage, in preparation).

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The effects of geographic range size and abundance on extinction during a time of “sluggish”’ evolution

Paleobiology ◽

10.1017/pab.2020.52 ◽

2020 ◽

pp. 1-14

Author(s):

Michelle M. Casey ◽

Erin E. Saupe ◽

Bruce S. Lieberman

Keyword(s):

North American ◽

Fossil Record ◽

Extinction Risk ◽

Geographic Range ◽

Range Size ◽

Late Paleozoic ◽

The North ◽

Geographic Range Size ◽

The Relationship ◽

Habitat Tracking

Abstract Geographic range size and abundance are important determinants of extinction risk in fossil and extant taxa. However, the relationship between these variables and extinction risk has not been tested extensively during evolutionarily “quiescent” times of low extinction and speciation in the fossil record. Here we examine the influence of geographic range size and abundance on extinction risk during the late Paleozoic (Mississippian–Permian), a time of “sluggish” evolution when global rates of origination and extinction were roughly half those of other Paleozoic intervals. Analyses used spatiotemporal occurrences for 164 brachiopod species from the North American midcontinent. We found abundance to be a better predictor of extinction risk than measures of geographic range size. Moreover, species exhibited reductions in abundance before their extinction but did not display contractions in geographic range size. The weak relationship between geographic range size and extinction in this time and place may reflect the relative preponderance of larger-ranged taxa combined with the physiographic conditions of the region that allowed for easy habitat tracking that dampened both extinction and speciation. These conditions led to a prolonged period (19–25 Myr) during which standard macroevolutionary rules did not apply.

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The plant fossil record reflects just two great extinction events

Terra Nova ◽

10.1111/ter.12086 ◽

2013 ◽

Vol 26 (3) ◽

pp. 195-200 ◽

Cited By ~ 46

Author(s):

Borja Cascales-Miñana ◽

Christopher J. Cleal

Keyword(s):

Fossil Record ◽

Plant Fossil ◽

Extinction Events

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Were bivalves ecologically dominant over brachiopods in the late Paleozoic? A test using exceptionally preserved fossil assemblages

Paleobiology ◽

10.1017/pab.2019.3 ◽

2019 ◽

Vol 45 (02) ◽

pp. 265-279 ◽

Cited By ~ 1

Author(s):

Shannon Hsieh ◽

Andrew M. Bush ◽

J Bret Bennington

Keyword(s):

Fossil Record ◽

Energy Use ◽

Regional Scale ◽

Late Paleozoic ◽

Ecosystem Structure ◽

Relative Importance ◽

Clear Trend ◽

Fossil Assemblages ◽

Ecological Importance ◽

Preferential Dissolution

AbstractInterpreting changes in ecosystem structure from the fossil record can be challenging. In a prominent example, the traditional view that brachiopods were ecologically dominant over bivalves in the Paleozoic has been disputed on both taphonomic and metabolic grounds. Aragonitic bivalves may be underrepresented in many fossil assemblages due to preferential dissolution. Abundance counts may further understate the ecological importance of bivalves, which tend to have more biomass and higher metabolic rates than brachiopods. We evaluate the relative importance of the two clades in exceptionally preserved, bulk-sampled fossil assemblages from the Pennsylvanian Breathitt Formation of Kentucky, where aragonitic bivalves are preserved as shells, not molds. At the regional scale, brachiopods were twice as abundant as bivalves and were collectively equivalent in biomass and energy use. Analyses of samples from the Paleobiology Database that contain abundance counts are consistent with these results and show no clear trend in the relative ecological importance of bivalves during the middle and late Paleozoic. Bivalves were probably more important in Paleozoic ecosystems than is apparent in many fossil assemblages, but they were not clearly dominant over brachiopods until after the Permian–Triassic extinction, which caused the shelly benthos to shift from bivalve and brachiopod dominated to merely bivalve dominated.

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Neogene precipitation, vegetation, and elevation history of the Central Andean Plateau

Science Advances ◽

10.1126/sciadv.aaz4724 ◽

2020 ◽

Vol 6 (35) ◽

pp. eaaz4724 ◽

Cited By ~ 1

Author(s):

C. Martínez ◽

C. Jaramillo ◽

A. Correa-Metrío ◽

W. Crepet ◽

J. E. Moreno ◽

...

Keyword(s):

Fossil Record ◽

Climate Model ◽

Regional Climate ◽

High Elevation ◽

The Andes ◽

Plant Fossil ◽

History Of ◽

Andean Uplift ◽

Climate Model Simulations ◽

Fossil Data

Andean uplift played a fundamental role in shaping South American climate and species distribution, but the relationship between the rise of the Andes, plant composition, and local climatic evolution is poorly known. We investigated the fossil record (pollen, leaves, and wood) from the Neogene of the Central Andean Plateau and documented the earliest evidence of a puna-like ecosystem in the Pliocene and a montane ecosystem without modern analogs in the Miocene. In contrast to regional climate model simulations, our climate inferences based on fossil data suggest wetter than modern precipitation conditions during the Pliocene, when the area was near modern elevations, and even wetter conditions during the Miocene, when the cordillera was around ~1700 meters above sea level. Our empirical data highlight the importance of the plant fossil record in studying past, present, and future climates and underscore the dynamic nature of high elevation ecosystems.

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Major Patterns in Botanical Diversity

The Paleontological Society Special Publications ◽

10.1017/s2475262200014076 ◽

1999 ◽

Vol 9 ◽

pp. 171-186

Author(s):

Peter R. Crane

Keyword(s):

Fossil Record ◽

Pollen Grains ◽

Terrestrial Ecosystems ◽

Plant Evolution ◽

Cambrian Explosion ◽

Fossil Plants ◽

Plant Parts ◽

Plant Fossil ◽

Public Consciousness ◽

The Rich

At a time when the popular perception of paleontology is dominated by images of dinosaurs and other spectacular vertebrates, or the mysteries surrounding the Cambrian “explosion” of animal life, it is perhaps not surprising that the rich and informative fossil record of plants has scarcely made an impact on the public consciousness. In reality, as one would expect from those organisms that comprise the bulk of the biological material in terrestrial ecosystems, the fossil record of plants is extensive (Stewart and Rothwell, 1993). Leaves, wood fragments, pollen grains, spores, fruits, seeds and other plant parts are the most common fossils in rocks deposited in ancient flood plains, lakes and many other environments - and they are often exquisitely preserved. This excellent fossil record provides important information about the ecology of ancient terrestrial ecosystems. The quality of the plant fossil record also makes paleobotanical data highly informative about the historical pattern of plant evolution. It is this pattern, and its congruence with patterns in the characters of living and fossil plants — as summarized in a classification — that is the focus of this chapter.

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Evidence of oribatid mite detritivory in Antarctica during the late Paleozoic and Mesozoic

Journal of Paleontology ◽

10.1017/s002233600004395x ◽

2004 ◽

Vol 78 (6) ◽

pp. 1146-1153 ◽

Cited By ~ 13

Author(s):

Derek W. Kellogg ◽

Edith L. Taylor

Keyword(s):

Fossil Record ◽

Oribatid Mite ◽

Late Paleozoic ◽

Transantarctic Mountains ◽

Animal Interaction ◽

Wood Boring

Despite their importance in breaking down lignified tissue today, much is still unknown about the role of mites in the fossil record, especially with reference to the Paleozoic–Mesozoic transition. This study examines permineralized peat from three localities in the central Transantarctic Mountains, ranging in age from Permian to Jurassic, for evidence of diversity and abundance of wood-boring mites. Evidence of mites, in the form of coprolites and tunnels in wood and other tissues, was found at all three localities; the Triassic site included more than 10 times as many wood borings as the Permian site. Our results supplement prior evidence of wood-boring mites during the Mesozoic and thereby fill in the known geologic range of this plant/animal interaction.

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Leaf surface development and the plant fossil record: stomatal patterning in Bennettitales

Biological Reviews ◽

10.1111/brv.12497 ◽

2019 ◽

Vol 94 (3) ◽

pp. 1179-1194 ◽

Cited By ~ 4

Author(s):

Paula J. Rudall ◽

Richard M. Bateman

Keyword(s):

Fossil Record ◽

Leaf Surface ◽

Plant Fossil ◽

Surface Development ◽

Stomatal Patterning

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Paleocommunity and evolutionary ecology of Paleozoic crinoids

The Paleontological Society Papers ◽

10.1017/s1089332600000218 ◽

1997 ◽

Vol 3 ◽

pp. 69-106 ◽

Cited By ~ 9

Author(s):

Peter F. Holterhoff

Keyword(s):

Beta Diversity ◽

Fossil Record ◽

Evolutionary Ecology ◽

Alpha Diversity ◽

High Energy ◽

Late Ordovician ◽

Low Energy ◽

Late Paleozoic ◽

Common Component ◽

Early Diversification

Crinoids were a common component of Paleozoic benthic paleocommunities, yet they have been under-utilized in paleoecological analyses. Recent efforts to incorporate disarticulated ossicles into these analyses have greatly increased the robustness of paleoecological patterns noted for the Crinoidea. Analyses of crinoid functional morphology, particularly filtration dynamics, have provided testable hypotheses concerning the distribution of crinoids among benthic environments. These models predict that crinoids with dense-mesh filtration fans should be most common in high energy, shoreward paleoenvironments, whereas open-fan crinoids should be most common in low-energy, offshore paleoenvironments. Review of the Paleozoic fossil record appears to support these general predictions—from the Late Ordovician to the end of the Paleozoic, dense-fan crinoids are most abundant in nearshore paleoenvironments, whereas open-fan crinoids are most abundant offshore.The partitioning of crinoid diversity through the Paleozoic shifted through time. Beta diversity was highest in the Ordovician, implying that the early diversification of crinoids was focused on partitioning the benthic landscape among taxa. Beta diversity was quite low by the late Paleozoic, however, local and within-habitat alpha diversity was much greater than during the Ordovician. This resulted in generally higher levels of eurytopy in the late Paleozoic compared to the Ordovician. Patterns of faunal disassembly associated with regional extinctions in North America during the Ordovician and Permian underscore the differences in the paleoecology of these crinoid faunas.

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