scholarly journals The importance of paraphyletic groups in mammalian paleobiology

1992 ◽  
Vol 6 ◽  
pp. 148-148
Author(s):  
Christine Janis
Keyword(s):  
Environmental Changes ◽  
Late Eocene ◽  
Foraging Strategies ◽  
Practical Reasons ◽  
Phylogenetic Systematics ◽  
The Status ◽  
Early Neogene ◽  
Drying Trend ◽  
Cladistic Taxonomy ◽  
Early Paleogene

The introduction of cladistic techniques in phylogenetic systematics have revolutionized many concepts in mammalian taxonomy: most notably, many early groups have been relegated to the status of paraphyletic or polyphyletic assemblages (e.g. the “Condylarthra” or “stem ungulates” and the “Proteutheria” insectivorans.). While it is important to recognize truly polyphyletic groups (e.g. the “Amblypoda” or Paleogene “pachyderm” analogs), all non-monophyletic groups are now commonly assigned to a similar “wastebasket” status, rendering all events associated with their evolution as “pseudo-events” on the grounds of taxonomic impurity.I am uncomfortable with this tendency for two reasons. The first is philosophical. Monophyly is a time-dependent system of classification: all taxa were monophyletic at their inception and the more successful (i.e. generative) ones must inevitably pass into paraphyly. Cladistic taxonomy claims to be independent of stratigraphic bias, but seemingly has no problem with using an arbitrary cut-off point in the geological record (the Recent) as a means of imposing taxonomic nomenclature. The second is for practical reasons concerning information contained in many of these paraphyletic taxa that is relevant to issues other than phylogenetic systematics.I examine closely the evolutionary histories of early Paleogene “miacoid” carnivores and late Paleogene “gelocid” artiodactyls. The extinction of miacoid species in the Late Eocene (giving rise to families of larger, apparently more actively hunting carnivores) and the extinction of gelocid species in the Late Oligocene (giving rise to families of larger ruminants apparently better equipped to ingest and process fibrous vegetation) were both coincident with major climatic and environmental changes. The change from non-seasonal to seasonal climates in the Northern hemisphere in the late Eocene may have influenced a change in predator adaptive strategies; likewise, the drying trend and spread of more open habitats in the early Neogene may have influenced ruminant foraging strategies. I submit that while not all paraphylectic groups may be useful in this fashion, at least in the above instances much paleobiological information is lost if these groups are dismissed because of their paraphyletic status: their demise reflects not artificial “pseudoextinction” but rather a real loss of archaic adaptations in a changing world.

Historical Changes in Large River Fish Assemblages of the Americas

2005 ◽  
Keyword(s):  
Alien Species ◽  
Environmental Changes ◽  
Fish Assemblages ◽  
Fish Fauna ◽  
Large River ◽  
Gold Rush ◽  
Physical Habitat ◽  
San Joaquin River ◽  
The Status ◽  
Native Fishes

<em>Abstract.</em>—In this paper, we review information regarding the status of the native fishes of the combined Sacramento River and San Joaquin River drainages (hereinafter the “Sacramento–San Joaquin drainage”) and the factors associated with their declines. The Sacramento–San Joaquin drainage is the center of fish evolution in California, giving rise to 17 endemic species of a total native fish fauna of 28 species. Rapid changes in land use and water use beginning with the Gold Rush in the 1850s and continuing to the present have resulted in the extinction, extirpation, and reduction in range and abundance of the native fishes. Multiple factors are associated with the declines of native fishes, including habitat alteration and loss, water storage and diversion, flow alteration, water quality, and invasions of alien species. Although native fishes can be quite tolerant of stressful physical conditions, in some rivers of the drainage the physical habitat has been altered to the extent that it is now more suited for alien species. This interaction of environmental changes and invasions of alien species makes it difficult to predict the benefits of restoration efforts to native fishes. Possible effects of climate change on California’s aquatic habitats add additional complexity to restoration of native fishes. Unless protection and restoration of native fishes is explicitly considered in future water management decisions, declines are likely to continue.

scholarly journals Achieving similar root microbiota composition in neighbouring plants through airborne signalling

2020 ◽  
Author(s):  
Hyun Gi Kong ◽  
Geun Cheol Song ◽  
Hee-Jung Sim ◽  
Choong-Min Ryu
Keyword(s):  
Microbial Community ◽  
Environmental Changes ◽  
Tomato Seedling ◽  
Environmental Signals ◽  
Plant Volatile ◽  
The Status ◽  
Plant Growth Promoting ◽  
The Impact ◽  
First Time ◽  
Rhizosphere Microbial Community

Abstract The ability to recognize and respond to environmental signals is essential for plants. In response to environmental changes, the status of a plant is transmitted to other plants in the form of signals such as volatiles. Root-associated bacteria trigger the release of plant volatile organic compounds (VOCs). However, the impact of VOCs on the rhizosphere microbial community of neighbouring plants is not well understood. Here, we investigated the effect of VOCs on the rhizosphere microbial community of tomato plants inoculated with a plant growth-promoting rhizobacterium Bacillus amyloliquefaciens strain GB03 and that of their neighbouring plants. Interestingly, high similarity (up to 69%) was detected in the rhizosphere microbial communities of the inoculated and neighbouring plants. Leaves of the tomato plant treated with strain GB03-released β-caryophyllene as a signature VOC, which elicited the release of a large amount of salicylic acid (SA) in the root exudates of a neighbouring tomato seedling. The exposure of tomato leaves to β-caryophyllene resulted in the secretion of SA from the root. Our results demonstrate for the first time that the composition of the rhizosphere microbiota in surrounding plants is synchronized through aerial signals from plants.

scholarly journals A Review of Earth Observation-Based Analyses for Major River Basins

2019 ◽  
Vol 11 (24) ◽  
pp. 2951 ◽  
Author(s):  
Soner Uereyen ◽  
Claudia Kuenzer
Keyword(s):  
Land Surface ◽  
Spatial Databases ◽  
Spatial Information ◽  
Environmental Changes ◽  
River Basins ◽  
Global Scale ◽  
Earth Observation ◽  
Basin Scale ◽  
The Status ◽  
Major River

Regardless of political boundaries, river basins are a functional unit of the Earth’s land surface and provide an abundance of resources for the environment and humans. They supply livelihoods supported by the typical characteristics of large river basins, such as the provision of freshwater, irrigation water, and transport opportunities. At the same time, they are impacted i.e., by human-induced environmental changes, boundary conflicts, and upstream–downstream inequalities. In the framework of water resource management, monitoring of river basins is therefore of high importance, in particular for researchers, stake-holders and decision-makers. However, land surface and surface water properties of many major river basins remain largely unmonitored at basin scale. Several inventories exist, yet consistent spatial databases describing the status of major river basins at global scale are lacking. Here, Earth observation (EO) is a potential source of spatial information providing large-scale data on the status of land surface properties. This review provides a comprehensive overview of existing research articles analyzing major river basins primarily using EO. Furthermore, this review proposes to exploit EO data together with relevant open global-scale geodata to establish a database and to enable consistent spatial analyses and evaluate past and current states of major river basins.

scholarly journals Population status and feeding behavior of black kite (Milvus migrans) in Dhaka city, Bangladesh

2021 ◽  
Vol 9 (1-2) ◽  
pp. 35-48
Author(s):  
Md Amdadul Haque ◽  
Rasel Ahammed ◽  
Monirujjaman ◽  
Md Abraharul Islam ◽  
Md Nahid H Khan ◽  
...  
Keyword(s):  
Population Density ◽  
Feeding Behavior ◽  
Sampling Method ◽  
Population Estimation ◽  
Foraging Strategies ◽  
Dhaka City ◽  
Population Status ◽  
Milvus Migrans ◽  
Black Kite ◽  
The Status

The status and feeding behavior of black kite (Milvus migrans) in Dhaka city were studied from July 2015 to June 2017. Road transects and morning roost-count method were used for population estimation and distribution, whereas focal sampling method was used to study the feeding and foraging behavior. Based on roosting and foraging areas, five transects were selected for population estimation. Moreover, six different feeding areas were selected for identifying various types of consumed food and assessing the feeding behavior of black kite. The black kite population was estimated at (1296±5.87) in Dhaka city. The population density was estimated at 21.8/km2. Among selected five different transects, the recorded population ranged from 108.12±6.70, 8.34%) at S-3 (Mirpur to Ramna Park) to 805±11.88, 62.11% of individuals at S-5 (Gulistan to Demra). The present study revealed that black kites were distributed throughout the study area and the distribution was influenced by availability of food, water and roosting place. Based on the annual records, the highest population (1510±6.92) was found in 2016. Majority of black kites fed on offal and insects in study area. In garbage dumps, the highest rate of feeding was recorded in afternoon followed by in morning and lowest in the noon. Whereas in non-garbage feeding areas, the highest rate was recorded in the morning followed by in the afternoon and lowest in the noon. Among four different foraging strategies, food collection by kites standing on the ground and intraspecific cleptoparasitism was never observed during study period while interspecific cleptoparasitism (against crows) was the highest number (193.67±2.77, 68.43%). Jahangirnagar University J. Biol. Sci. 9(1 & 2): 35-48, 2020 (June & December)

scholarly journals Use of an embedded fruit by Nicobar Long-tailed Macaque Macaca fascicularis umbrosus: II. Demographic influences on choices of coconuts Cocos nucifera and pattern of forays to palm plantations

2020 ◽  
Vol 12 (11) ◽  
pp. 16407-16423
Author(s):  
Sayantan Das ◽  
Rebekah C. David ◽  
Ashvita Anand ◽  
Saurav Harikumar ◽  
Rubina Rajan ◽  
...  
Keyword(s):  
Macaca Fascicularis ◽  
Environmental Changes ◽  
Cocos Nucifera ◽  
Food Resource ◽  
Foraging Strategies ◽  
Life History Strategies ◽  
Forest Plantation ◽  
Age Classes ◽  
Patterns Of Use ◽  
Demographic Patterns

Adaptive pressures of human-induced rapid environmental changes and insular ecological conditions have led to behavioral innovations among behaviorally flexible nonhuman primates.  Documenting long-term responses of threatened populations is vital for our understanding of species and location-specific adaptive capacities under fluctuating equilibrium.  The Nicobar Long-tailed Macaque  Macaca fascicularis umbrosus, an insular sub-species uses coconuts Cocos nucifera, an embedded cultivar as a food resource and is speculated to have enhanced its dependence as a result of anthropogenic and environmental alterations.  We explored demographic patterns of use and abandonment of different phenophases of fresh coconuts.  To study crop foraging strategies, we recorded daily entry and duration of forays into coconut plantations.  We divided age-classes into early juvenile (13–36 months), late juvenile (37–72 months), and adults (>72 months) and classified phenophase of coconuts into six types.  Consistent with the theory of life history strategies, late juveniles were found to use a greater number of coconuts, which was considerably higher in an urban troop but marginally higher in a forest-plantation dwelling group.  Except in late juveniles, males consumed a higher number of coconuts than females in the remaining age-classes.  Owing to developmental constraints, juveniles of both types used higher proportion of immature coconuts though adults showed equitable distribution across phenophases.  Pattern of entries to plantations and duration of forays were uniform through the day in the urban troop but modulatory in the forest-plantation group, perhaps due to frequent and hostile human interferences.  Observations corroborating adaptations to anthropogenic disturbances are described. 

scholarly journals Developing a Robust Strategy Map in Balanced Scorecard Model Using Scenario Planning

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Mostafa Jafari ◽  
Kamran Shahanaghi ◽  
Majid Tootooni
Keyword(s):  
Balanced Scorecard ◽  
Environmental Changes ◽  
Scenario Planning ◽  
Status Quo ◽  
Strategy Implementation ◽  
Post Office ◽  
The Status ◽  
Strategy Map ◽  
Past Data ◽  
Over Time

The key to successful strategy implementation in an organization is for people in the organization to understand it, which requires the establishment of complicated but vital processes whereby the intangible assets are converted into tangible outputs. In this regard, a strategy map is a useful tool that helps execute this difficult task. However, such maps are typically developed based on ambiguous cause-effect relationships that result from the extrapolation of past data and flawed links with possible futures. However, if the strategy map is a mere reflection of the status quo but not future conditions and does not embrace real-world uncertainties, it will endanger the organization since it posits that the current situation will continue. In order to compensate for this deficiency, the environmental scenarios affecting an organization were identified in the present study. Then the strategy map was developed in the form of a scenario-based balanced scorecard. Besides, the effect of environmental changes on the components of the strategy map was investigated using the strategy maps illustrated over time together with the corresponding cash flow vectors. Subsequently, a method was proposed to calculate the degree of robustness of every component of the strategy map for the contingency of every scenario. Finally, the results were applied to a post office.

scholarly journals Eocene to Oligocene nannofossils stratigraphy and environmental conditions in Izeh Province, Zagros Basin, East Tethys

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Saeedeh Senemari ◽  
Farah Jalili
Keyword(s):  
Environmental Changes ◽  
Late Eocene ◽  
Marine Phytoplankton ◽  
Asmari Formation ◽  
Calcareous Nannofossils ◽  
Calcareous Nannofossil ◽  
Southwestern Iran ◽  
Pabdeh Formation ◽  
First Time ◽  
Palaeoenvironmental Conditions

AbstractData obtained from the calcareous nannofossils, distributed in the upper part of the Pabdeh Formation (Priabonian–Rupelian) and the lower part of the Asmari Formation (Chattian) in the Bid-Zard section, were used to investigate the Eocene to Oligocene palaeoenvironmental conditions in the southwest of Izeh, southwestern Iran (eastern Tethys). The upper part of the Pabdeh Formation was composed of shale, thin-bedded pelagic limestone and dolostone, which is disconformably overlain by the Asmari Formation. For the first time, 29 species of calcareous nannofossils belonging to 13 genera were identified in the studied section. The calcareous nannofossils in the upper part of the Pabdeh Formation indicate the Isthmolithus recurvus Zone/Sphenolithus pseudoradians Zone (combined zone), Ericsonia subdisticha Zone, Helicosphaera reticulata Zone and Sphenolithus praedistentus Zone, from the Priabonian to the Rupelian. The Sphenolithus ciperoensis Zone of the Chattian was identified in the lower part of the Asmari Formation. Calcareous nannofossil stratigraphy across the upper Eocene–Oligocene interval also reveals a disconformity at the Rupelian/Chattian transition due to a bio-event. Shallowing of the basin and environmental changes in this part of the Tethyan domain could have led to the lithostratigraphic and biostratigraphic changes. In fact, during the late Eocene to late Oligocene, marine phytoplankton was sensitive to climate changes such as decreasing temperature, as well as possibly to a nutrient increase and changes in basin depth.

scholarly journals Similar foraging energetics of two sympatric albatrosses despite contrasting life histories and wind-mediated foraging strategies

2020 ◽  
Vol 223 (23) ◽  
pp. jeb228585 ◽  
Author(s):  
Caitlin E. Kroeger ◽  
Daniel E. Crocker ◽  
Rachael A. Orben ◽  
David R. Thompson ◽  
Leigh G. Torres ◽  
...  
Keyword(s):  
Energy Balance ◽  
Life Histories ◽  
Behavioral Plasticity ◽  
Environmental Changes ◽  
Behavioral Flexibility ◽  
Mass Gain ◽  
Central Place ◽  
Foraging Strategies ◽  
Wind Speeds ◽  
Ocean Environment

ABSTRACTUnderstanding the environmental and behavioral factors that influence how organisms maintain energy balance can inform us about their potential resiliency to rapid environmental changes. Flexibility in maintaining energy balance is particularly important to long-lived, central-place foraging seabirds that are constrained when locating food for offspring in a dynamic ocean environment. To understand the role of environmental interactions, behavioral flexibility and morphological constraints on energy balance, we used doubly labeled water to measure the at-sea daily energy expenditure (DEE) of two sympatrically breeding seabirds, Campbell (Thalassarche impavida) and grey-headed (Thalassarchechrysostoma) albatrosses. We found that species and sexes had similar foraging costs, but DEE varied between years for both species and sexes during early chick rearing in two consecutive seasons. For both species, greater DEE was positively associated with larger proportional mass gain, lower mean wind speeds during water take-offs, greater proportions of strong tailwinds (>12 m s−1), and younger chick age. Greater proportional mass gains were marginally more costly in male albatrosses that already have higher wing loading. DEE was higher during flights with a greater proportion of strong headwinds for grey-headed albatrosses only. Poleward winds are forecasted to intensify over the next century, which may increase DEE for grey-headed albatrosses that heavily use this region during early chick rearing. Female Campbell albatrosses may be negatively affected by forecasted slackening winds at lower latitudes due to an expected greater reliance on less energy efficient sit-and-wait foraging strategies. Behavioral plasticity associated with environmental variation may influence future population responses to climate change of both species.

scholarly journals Fish proliferation and rare-earth deposition by topographically induced upwelling at the late Eocene cooling event

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Junichiro Ohta ◽  
Kazutaka Yasukawa ◽  
Tatsuo Nozaki ◽  
Yutaro Takaya ◽  
Kazuhide Mimura ◽  
...  
Keyword(s):  
Rare Earth ◽  
Environmental Changes ◽  
Deep Ocean ◽  
Late Eocene ◽  
Ocean Bottom ◽  
Isotope Record ◽  
Concentrated Source ◽  
Climate Transition ◽  
Central South ◽  
Osmium Isotope

Abstract The deep-sea clay that covers wide areas of the pelagic ocean bottom provides key information about open-ocean environments but lacks age-diagnostic calcareous or siliceous microfossils. The marine osmium isotope record has varied in response to environmental changes and can therefore be a useful stratigraphic marker. In this study, we used osmium isotope ratios to determine the depositional ages of pelagic clays extraordinarily rich in fish debris. Much fish debris was deposited in the western North and central South Pacific sites roughly 34.4 million years ago, concurrent with a late Eocene event, a temporal expansion of Antarctic ice preceding the Eocene–Oligocene climate transition. The enhanced northward flow of bottom water formed around Antarctica probably caused upwelling of deep-ocean nutrients at topographic highs and stimulated biological productivity that resulted in the proliferation of fish in pelagic realms. The abundant fish debris is now a highly concentrated source of industrially critical rare-earth elements.

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