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Little evidence for enhanced phenotypic evolution in early teleosts relative to their living fossil sister group

Little evidence for enhanced phenotypic evolution in early teleosts relative to their living fossil sister group

The Broader Holostean Radiation Does Not Fulfill Numerous Living Fossil Expectations. Darwin articulated several concepts of what it means to be a living fossil (2), such as taxa that are “remnants of a once preponderant order,” or are “slowly formed” (i.e., showing low rates of lineage diversification or trait evolution). Extant holosteans, which are among Darwin’s archetypal living fossils (2), embody these features clearly: they represent the last survivors of a once diverse radiation and demonstrate low rates of lineage diversification (26, 32, 35). The modern genera Amia, Lepisosteus, and Atractosteus show negligible anatomical change since their first appearance in the Late Cretaceous and Paleocene (1, 36), and living gars show low rates of body size evolution (17). In contrast to this pattern from living species, Mesozoic hol- osteans show comparable rates of size change to total- (Fig. 3A), crown- (Fig. S5A), and stem-group teleosts (Fig. S5B). These patterns are seen across a majority of topologies regardless of timescale. Rates of shape evolution in holosteans are broadly comparable to those of teleosts, but often exceed those of total- group teleosts on molecular timescales (Fig. 3A) and stem tele- osts on both timescales (Fig. S5B).
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The Complete DNA Sequence of the Mitochondrial Genome of a “Living Fossil,” the Coelacanth (Latimeria chalumnae)

The Complete DNA Sequence of the Mitochondrial Genome of a “Living Fossil,” the Coelacanth (Latimeria chalumnae)

Complete termination codons are indicated (*). tRNA genes are underlined and the corresponding anticodons are overlined. In the control region, four repeats are shown.. Ba[r]

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The Penalty of a Long, Hot Summer. Photosynthetic Acclimation to High CO2 and Continuous Light in “Living Fossil” Conifers

The Penalty of a Long, Hot Summer. Photosynthetic Acclimation to High CO2 and Continuous Light in “Living Fossil” Conifers

We examined the seasonal pattern of photosynthe- sis to investigate the characteristics of this paradox. Photosynthesis may be lower in evergreen than de- ciduous leaves for a number of reasons: internal shading and diffusional limitation by strengthening tissues, investment in defense against herbivores rather than photosynthetic proteins, or low stomatal conductance to conserve water during drought (Reich et al., 1999). However, our study emphasized the physiological mechanisms underlying seasonal changes in photosynthesis and the action of elevated pCO 2 . We examined three closely related “living fos- sil” species of conifer: the evergreen coastal redwood
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Unspecified #3009027

Unspecified #3009027

You may find it helpful to use sections of the video-recording of the BBC TV programme 'Invasion of the Land' (from Attenborough's 'Life on Earth' series) as an additional resource. An extension activity could be to ask students to work in groups to design a poster on the theme “The living fossil named Old Four-Legs”.

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The Urge to Merge: Ritual Insult and the Evolution of Syntax

The Urge to Merge: Ritual Insult and the Evolution of Syntax

Doubt has been expressed that complex syntactic patterns conferred communi- cative benefits on our evolutionary ancestors and, therefore, evolved by way of natural or sexual selection (e.g., Bickerton 1990, 1998, Lightfoot 1991, Berwick 1998, Newmeyer 2003). This doubt comes primarily from the observation that the principles of grammar, especially syntax, seem rather abstract and arbitrary, and are thus not easily amenable to evolutionary forces such as selection. Under the circumstances, it makes sense to look elsewhere for an explanation, such as verbal complexity or display (Locke 2008, 2009), or to consider the most basic (proto-)syntactic combinations (Progovac 2006, 2008, 2009). Here, we consider the possibility that a specific form of ‘proto-syntax’ evolved in a context that included a particular type of verbal display — ritual insult. We present a type of compound, the exocentric compound, which can be seen as a ‘living fossil’ of this stage of proto-syntax. While our paper cannot provide physical proof that sexual selection played a role in reinforcing proto-syntax, it points to places where such
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Monoplacophorans and the Origin and Relationships of Mollusks

Monoplacophorans and the Origin and Relationships of Mollusks

While much work remains to be done to further resolve the monoplacophoran's position on the molluscan Tree of Life, there also needs to be recognition of the innovative and integrative research approaches that these curious animals have attracted. J. B. Knight (1952), who would interpreted monoplacophorans as non-torted, primitive mollusks and grouped them with the chitons and aplacophorans, did this by integrating stratigraphic data from the fossil record with both anatomical and functional studies of living taxa and ontogenetic data from developmental studies. He then worked back through time, what he referred to as “climbing down the family tree,” using data from living taxa to incorporate less well-known extinct forms into his evolu- tionary scenario. From these reconstructions, he then moved to other branches and reclimbed his tree looking for concurrence of characters across his evolutionary scenario. Four years after Knight's innovative use of paleontological and neontological data to construct hypotheses of molluscan evolution, the discovery of N. galatheae validated his interpretation of Tryblidium, and invertebrate zoologists and malacologists anointed the newly discovered limpets from the abyssal plains off Costa Rica as a living fossil. While the living fossil designation remains ambiguous, the methodol- ogy that J. B. Knight and others have employed in the study of these unique mollusks has been validated.
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Analysis of Thermal Effects on Valve by Conventional and Blended Fuels

Analysis of Thermal Effects on Valve by Conventional and Blended Fuels

warmed in some sort of heater. Frosts are generally controlled by vitality thick fills, for example, gas or diesel, fluids got from fossil energizes. While there are numerous stationary applications, most ICEs are utilized as a part of versatile applications and are the prevailing force supply for autos, flying machine, and pontoons. All interior burning motors rely on upon ignition of a compound fuel, ordinarily with oxygen from the air (however it is conceivable to infuse nitrous oxide to accomplish business as usual thing and increase a force help). The ignition procedure ordinarily brings about the generation of an incredible amount of warmth, and in addition the creation of steam and carbon dioxide and different chemicals at high temperature; the temperature came to is controlled by the concoction cosmetics of the fuel and oxidizers (see stoichiometry), and also by the pressure and different elements.
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Possible Occurrence Of Cretaceous - Eocene Rocks in the Continental Shelf Edge, off Madras

Possible Occurrence Of Cretaceous - Eocene Rocks in the Continental Shelf Edge, off Madras

It is likely that the fossil cast and the fossil bearing phosphatic rocks are derived from the Upper Cretaceous- Eocene sedimentary sequence occurring on the seabed in the shelf edg[r]

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Brocchi’s Subapennine Fossil Conchology

Brocchi’s Subapennine Fossil Conchology

tions. Some time after writing a “Treatise on Odiferous Plants” in 1796 (he remained interested in botany for the rest of his life), Brocchi focused on geology in 1802, when he wrote a mineralogical account on a sector of Lombardy. In the same year, he was appointed to teach mineralogy at the Brescia Lyceum, presenting in his Mineralogical Lectures the first comparison of fossil and living invertebrates. Thanks to his acquaintance with the work of early marine zoologists like the young Giuseppe Olivi (1769–1795), he could access existing reports on the Mediterranean fauna. In the “Mineralogical Lectures,” he could thus come to propose that “many species of petrified crustaceans are not met with alive in modern seas.” This was a first argument against one general belief of his time, championed first by Carl Linneaus and then Jean Guillaume Bruguière, that all fossil species unknown in the modern biota are living in some remote part of the globe. By 1802, Brocchi was discovering on his own ground the reality of extinction of marine species, as Georges Cuvier was doing for Tertiary terrestrial mammals of the Paris Basin (Rudwick 2005). He could also be influenced by Lamarck’s teachings in Paris, if not by his monograph on Tertiary mollusks, which appeared between 1802 and 1809. In fact, if Brocchi was never in Paris, still he kept very good connections there through the naturalist Giuseppe Marzari-Pencati from Venice, one who attended Lamarck’s lectures in 1803 and who regularly sent Brocchi materials and books from the capital of geology (Pancaldi 1991).
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Biodiesel: A Future fuel (A Review)

Biodiesel: A Future fuel (A Review)

Due to the concern on the availability of recoverable fossil fuel reserves and the environmental problems caused by the use those fossil fuels, considerable attention has been given to biodiesel production as an alternative to petro diesel. The general way to produce biodiesel fuel is by Transesterification of vegetable oil with methanol in the presence of either alkaline or strong acid catalysts. Transesterification reaction is quite sensitive to various parameters. An ideal Transesterification reaction differs on the basis of variables such as fatty acid composition and the free fatty acid content of the oil. The benefits of biodiesel go far beyond the clean burning nature of the product. Bio diesel is a renewable resource helping to reduce the dependence of the economy on limited resources and imports, create a market for farmers and reduce the amount of waste oil, fat and grease being dumped into landfills and sewers. This paper reviews the production and use of Biodiesel fuel as an alternative fuel for existing IC engines. Keywords: biodiesel, Transesterification, economy, IC engines, fuel.
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The Brandy Creek fossil flora

The Brandy Creek fossil flora

The Eocene (55.8 – 33.9 million years before present) was a warm interval during which the world’s biota evolved into forms recognisable today and the Northern Hemisphere continents adopted their current positions (Wing and Greenwood 1993; Zachos, Stott and Lohmann 1994; Greenwood and Wing 1995). Australia at this time during the Eocene lay well south of its current position and adjacent to Antarctica, but separated from Antarctica by a water gap as far east as what is now Tasmania, with this connection severing during the Eocene (Quilty 1994; Pross et al. 2012). This warm interval has been used as a benchmark for understanding climates warmer than those of today, and provides the means to understand better understand trends in current global warming climate and how these can affect ecosystems (Gajewski 1993; Zachos et al. 2008; Smith et al. 2012). Fossil and other evidence from Australia and North America indicate that Eocene forests grew close to the poles and that many organisms, typical of modern tropical environments such as palms and crocodiles, occupied areas that are currently too cold to support them (Willis and Molnar 1991; Markwick 1994, 1998; Greenwood and Wing 1995; Francis et al. 2008; Huber and Caballero 2011; Eberle & Greenwood 2012; Pross et al. 2012).
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Energy from Fossil Fuels.pdf

Energy from Fossil Fuels.pdf

dispersed, burn no volatile fuels, produce no radioactive fallout in the event of an attack, and require less of the infrastructure that delivers fuel and transmits electricity that makes our current system so vulnerable. Through efficiency and clean energy, we could, between now and 2020, avoid building 975 new power plants, retire 180 coal plants, and close 14 nuclear plants. Hundreds of thousands of miles of new gas pipelines would not be necessary. Independent studies show that renewable energy delivers more jobs per dollar than investments in fossil fuel plants. The Department of Energy estimates that harnessing just 5 percent of our energy from wind by 2020 would create 80,000 new jobs.
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Digitized Fossil Brains: Neocorticalization

Digitized Fossil Brains: Neocorticalization

A general point about the data of Figure 6. We see how primates are all ‘above average’. I do not label the data on other groups in this graph. I could have identified a dozen species of equids, for example, which are first known in the fossil record of about 55 Ma. A side issue for us, they have been ‘average’ (near the regression line) for most of their evolutionary history. Marsupials as a group have always been ‘below average’ as have most of the fossil Neotropical species of South America. These are secondary matters for biolinguistics but appropriate for a broad picture. For this report I present the data most relevant for the evolution of language, in particular in the human species. I place my statistical words in quotation marks to acknowledge the questionable theoretical status of my regression analysis.
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Biofuels as an Alternate Energy Source- A survey

Biofuels as an Alternate Energy Source- A survey

As data suggests the total primary energy demand of India is expected to increase by almost 150% by 2035. The mainstay of India’s energy sector is coal and fossil fuels; which are accounts for more than 50% of primary commercial energy supply. The coal based thermal power stations accounts for 69% of total primary energy supply (TPES). In addition to that around 50% of coal and more than 70% crude oil requirements are met from imports, which are also likely to increase due to depletion of these resources in forth coming years. The demand of fossil fuels will increase recently because the generation of energy and the total transportation business is depend upon the fossil fuels which are non renewable sources and also emits the greenhouse gases.
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Macroevolution with living and fossil species

Macroevolution with living and fossil species

Figure 2.7: The effects of increasing missing data on topological recovery using Maximum Likelihood trees black, Bayesian consensus trees grey, Maximum Likelihood bootstrap trees orange [r]

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Two fossil species of Metrosideros (Myrtaceae) from the Oligo Miocene Golden Fleece locality in Tasmania, Australia

Two fossil species of Metrosideros (Myrtaceae) from the Oligo Miocene Golden Fleece locality in Tasmania, Australia

2) Five main veins in the hypanthium - The most important character for identification for both fossil taxa is the presence of five main veins in the hypanthium, terminating in the sepals. This is a synapomorphy for the tribe Metrosidereae as defined by Wilson (2011). It is not the case that the fruits of all Metrosidereae ONLY have five veins, but that there are five major vascular traces. Remnants of the tops and bottoms of intermediate, non-major veins can be seen between the main veins in some extant Metrosideros post-dehiscence (Fig. 6 J2,K). The character of five, persistent and highly conspicuous externally visible veins running along the hypanthium is a feature commonly seen in the genus Tepualia (Dawson, 1972b) , and the (formerly) broadly defined Metrosideros subgenus Mearnsia (Dawson, 1970b, 1972a) (Fig. 6). It is now unlikely that what has been called subgenus Mearnsia is a monophyletic group (Pillon et al., 2015), so we cannot suggest subgeneric affinities other than to comment that they do not have any characters which suggest placement in subgenus Metrosideros, as we could with M. leunigii (Tarran et al., 2016).
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Protein sequences bound to mineral surfaces persist into deep time

Protein sequences bound to mineral surfaces persist into deep time

The eggshell at Laetoli are surface finds, but visual examinations show no evidence of rolling, transportation or weathering (having been exposed on the surface for only a very short period of time after having eroded out of the sediment). As a consequence, there is no likelihood of long-dis- tance transport. The location and preservation of the fossils, the absence of significant spatial dis- placement of surface finds, the short stratigraphic sections at each collecting spot, and the identification of the fossil-bearing horizons in each of those sections, allow the fossils to be placed quite precisely in their original stratigraphic context. The age and stratigraphy given for each of the samples can be assigned with a high degree of confidence. There are no lava flows in stratigraphic proximity or direct superposition to the stratigraphic units from which the Lower Laetolil and Upper Ndolanya specimens were recovered. Given that more than 40 m of consolidated sediment, and a time difference of 1.5 million years, separate the overlying lava flow (the Ogol Lavas) from the stra- tum from which the Upper Laetolil fossils were obtained, and that the intervening fossil-bearing beds show no geological evidence of having been impacted by heating, we do not believe that the samples have been exposed to additional heating that would have made them thermally older than we predict (Table 7).
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Protein sequences bound to mineral surfaces persist into deep time

Protein sequences bound to mineral surfaces persist into deep time

For fossil eggshell samples the extent of degradation, quantified by chiral amino acid analysis (AAR), shows that both hydrolysis and racemization increase with time, and that racemic equilibrium is reached in samples older than 1 Ma (~3.6 Ma@10 ˚ C; Figure 2; and Appendix 4—table 1 and 2). As degradation proceeds, the complexity of the proteome decreases, until only SCA-1 and SCA-2 are detected by LC-MS/MS in the oldest samples (Supplementary file 1). These two proteins are extremely well preserved in samples up to 150,000 years old, but by 3.8 Ma few peptides are recov- ered (Figure 3, Figure 3—figure supplement 1 and 2). A total of 22 peptide sequences was recov- ered from SCA-1 & SCA-2 in samples from Laetoli (Appendix 5, section A; Supplementary file 2), consistent with the idea that dehydration, in addition to mineral binding, may also play a role in retarding degradation of non-binding peptides (Collins and Riley, 2000). However, 80% of the spec- tra, consistently identified in ten independent LC-MS/MS analyses of three ostrich eggshell samples Table 2. Binding of proteins to the (10.4) calcite surface. The binding energies calculated as (a) mean for the full protein (by
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Leaf energy balance modelling as a tool to infer habitat preference in the early angiosperms

Leaf energy balance modelling as a tool to infer habitat preference in the early angiosperms

Sensitivity analysis indicates that environmental factors have a far greater impact on leaf temperature with increasing leaf size, indicating that habitat preference for sun or shade would be more critical in larger leaved species. Modelled fossil leaf temperature indicates that the small size of many early angiosperm leaves could have compensated for their low transpirational cooling capacity and enabled survival in full sun. These results, while not invalidating the dark and disturbed hypothesis, are consistent with evidence for early angiosperms possessing a range of ecological diversity that included plants of both shaded and open habitats.
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Development Of A Spent Oil-Fired 100 Kg Crucible Furnace For Small Scale Foundry Industries

Development Of A Spent Oil-Fired 100 Kg Crucible Furnace For Small Scale Foundry Industries

The available furnaces have been posed with the problem of fueling; coke, furnace oil which is a medium grade 2 oil and diesel being the most common fuel used in metal melting furnaces has been expensive, thereby making the available furnaces expensive to run.Energy plays a significant role in boosting economic growth, and the demand for fossil fuels continues to increase over the years [10]. The depletion of world oil reserves of fossil fuels leads to the development of biofuels and other alternatives sources of energy to substitute fossil fuels [11].Therefore the proposed crucible furnace will be exploring the viability of using spent engine oil and metal scraps will be sourced locally in order to reduce the cost of production thereby making it readily available for interested entrepreneur.
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