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2021 ◽  
Author(s):  
Stella Gerdemann ◽  
Annie E. Wertz

One key adaptive problem that humans had to solve was to identify safe plants while avoiding dangerous ones. The ability to reliably categorize plants was likely critical to accomplishing this task and avoid confusing non-toxic plants with similar-looking toxic ones. Here, we investigated which cues 18-month-old infants (Study 1, N = 40) from Germany, and adults (Study 2, N = 145) recruited online use to categorize plants and manmade artifacts. To this end, in Study 1, we presented infants with plants with different leaf shapes in brightly colored pots and feature-matched artifacts that had the same variation in shape and color as the plants. The results of the categorization task indicate that infants relied on variation in leaf shape to categorize plants more than they relied on similar variation in shape to categorize artifacts. In Study 2, using a modified version of the task from Study 1, we found that adults were less willing to categorize plants using features other than leaf shape, while they were more willing to do so for artifacts. We conclude that infants use different features to categorize plants and artifacts and that aspects of this categorization strategy persist into adulthood. The features infants use to categorize plants would have reliably differentiated between plant types over ancestral time and thus reliance on these features may be based on their conceptual relevance to plants.


2021 ◽  
Vol 288 (1943) ◽  
pp. 20202796
Author(s):  
Shikha Kalra ◽  
Vishruta Yawatkar ◽  
Logan S James ◽  
Jon T Sakata ◽  
Raghav Rajan

Numerous animal displays begin with introductory gestures. For example, lizards start their head-bobbing displays with introductory push-ups, and many songbirds begin their vocal displays by repeating introductory notes (INs) before producing their learned song. Among songbirds, the acoustic structure and the number of INs produced before song vary considerably between individuals in a species. While similar variation in songs between individuals is a result of learning, whether variations in INs are also due to learning remains poorly understood. Here, using natural and experimental tutoring with male zebra finches, we show that mean IN number and IN acoustic structure are learned from a tutor. Interestingly, IN properties and how well INs were learned, were not correlated with the accuracy of song imitation and only weakly correlated with some features of songs that followed. Finally, birds artificially tutored with songs lacking INs still repeated vocalizations that resembled INs, before their songs, suggesting biological predispositions in IN production. These results demonstrate that INs, just like song elements, are shaped both by learning and biological predispositions. More generally, our results suggest mechanisms for generating variation in introductory gestures between individuals while still maintaining the species-specific structure of complex displays like birdsong.


Rodriguésia ◽  
2021 ◽  
Vol 72 ◽  
Author(s):  
María Florencia Realini ◽  
Lidia Poggio ◽  
Julián Cámara-Hernández ◽  
Graciela Esther González

Abstract Variation in genome size and knob heterochromatin content was explored in relationship to altitudinal cline and length of the vegetative cycle in northern Argentina, USA and Mexico landraces. It was considering that the decrease in DNA and heterochromatin content could be an adaptation to a shorter growing season and the result of artificial selection by man. Guaraní landraces from Northeastern Argentina (NEA) show similar variation in genome size (3.81pg to 7.56pg) and knob heterochromatin content than maize growing across an altitudinal cline. The present analysis offers an overview of the genetic variability of NEA maize to explain why Guaraní landraces and those along an altitudinal cline share this similar variation. Karyotype and flow cytometry data were employed. The DNA content of Guaraní landraces which lacking B chromosomes, showed no significant relationship with knob heterochromatin, suggesting differences in the amount of interspersed DNA. A significant positive relationship was found between the length of the vegetative cycle and both number and percentage of knob heterochromatin. No significant correlation was found between genome size and vegetative cycle. All these results allow us to conclude that the variation in heterochromatin content among Guaraní maize is driven by the selection of farmers for flowering time.


2020 ◽  
Author(s):  
Shikha Kalra ◽  
Vishruta Yawatkar ◽  
Logan S James ◽  
Jon T Sakata ◽  
Raghav Rajan

ABSTRACTIntroductory gestures are present at the beginning of many animal displays. For example, lizards start their head-bobbing displays with introductory push-ups and animal vocal displays begin with introductory notes. Songbirds also begin their vocal displays by repeating introductory notes (INs) before producing their learned song and these INs are thought to reflect motor preparation. Between individuals of a given species, the acoustic structure of INs and the number of times INs are repeated before song varies considerably. While similar variation in songs between individuals is known to be a result of learning, whether INs are also learned remains poorly understood. Here, using natural and experimental tutoring with male zebra finches, we show that mean IN number and IN acoustic structure are learned from a tutor, independent of song learning. We also reveal biological predispositions in IN production; birds artificially tutored with songs lacking INs still repeated a short-duration syllable, thrice on average, before their songs. Overall, these results show that INs, just like elements in song, are shaped both by learning and biological predispositions and suggest multiple, independent, learning processes underlying the acquisition of complex vocal displays.


Author(s):  
Yvonne CF Su ◽  
Danielle E Anderson ◽  
Barnaby E Young ◽  
Feng Zhu ◽  
Martin Linster ◽  
...  

To date, the SARS-CoV-2 genome has been considered genetically more stable than SARS-CoV or MERS-CoV. Here we report a 382-nt deletion covering almost the entire open reading frame 8 (ORF8) of SARS-CoV-2 obtained from eight hospitalized patients in Singapore. The deletion also removes the ORF8 transcription-regulatory sequence (TRS), which in turn enhances the downstream transcription of the N gene. We also found that viruses with the deletion have been circulating for at least four weeks. During the SARS-CoV outbreak in 2003, a number of genetic variants were observed in the human population [1], and similar variation has since been observed across SARS-related CoVs in humans and bats. Overwhelmingly these viruses had mutations or deletions in ORF8, that have been associated with reduced replicative fitness of the virus [2]. This is also consistent with the observation that towards the end of the outbreak sequences obtained from human SARS cases possessed an ORF8 deletion that may be associated with host adaptation [1]. We therefore hypothesise that the major deletion revealed in this study may lead to an attenuated phenotype of SARS-CoV-2.


2019 ◽  
Author(s):  
Qian Chen ◽  
Xiaojing Ma ◽  
Chong Li ◽  
Yun Shen ◽  
Wei Zhu ◽  
...  

Abstract Background Type 2 diabetes (T2D) is a complex metabolic disease and has been proved to involve in the alternation of the gut microbiota. The previous studies primarily focused on the changes in bacteriome while ignoring the phage community composition. The extracellular phages could lyse the host bacteria, and thus influence the microbiota through the positive or negative interactions with bacteria. We investigated the change of extracellular phageome and explored its role in T2D pathogenesis.Results We used a sequencing-based approach to identify the bacteriophage after isolation of VLPs from the fecal samples. We identified 330 phages according to the predicted host bacteria. The phageome characteristics were highly diverse among individuals. In the T2D group, the intestinal phage population is altered and the abundance of 7 identified phages specific to Enterobacteriaceae hosts were found increased markedly. Additionally, the abundance of Enterobacteriaceae bacteria in gut was significantly increased and the systemic LPS elevation was observed in T2D group. Several phage consortia were found to have significant correlations with T2D disease indicators.Conclusions The alteration of bacteriophages predicted to infect Enterobacteriaceae in the gut was observed in this study, which was expected to be a new source of systemic LPS in T2D patients, and may contribute to the pathogenesis of the disease. The data present in this study revealed the similar variation trend in enteric bacteriome and the correlated bacteriophages, which is likely to shed considerable light on overall understanding the interactions between microbiome and metabolic diseases.


2019 ◽  
Vol 116 (13) ◽  
pp. 6045-6050 ◽  
Author(s):  
Thor Berger ◽  
Per Engzell

A large literature documents how intergenerational mobility—the degree to which (dis)advantage is passed on from parents to children—varies across and within countries. Less is known about the origin or persistence of such differences. We show that US areas populated by descendants to European immigrants have similar levels of income equality and mobility as the countries their forebears came from: highest in areas dominated by descendants to Scandinavian and German immigrants, lower in places with French or Italian heritage, and lower still in areas with British roots. Similar variation in mobility is found for the black population and when analyzing causal place effects, suggesting that mobility differences arise at the community level and extend beyond descendants of European immigrant groups. Our findings indicate that the geography of US opportunity may have deeper historical roots than previously recognized.


2019 ◽  
pp. 383-390
Author(s):  
William L Yancey ◽  
Walter J. Meyer ◽  
Lee C. Woodson ◽  
Rene Przkora

Treatment of pain in the burn patient presents a unique set of challenges. The pathology of pain with these injuries, while consistent at its most basic level, varies considerably with factors such as the burn severity and the stage of treatment/healing. The experience of pain shows similar variation. The assessment of pain and recognition of contributing factors such as anxiety and depression require vigilance and persistence, especially among paediatric populations. Multiple techniques for the measurement of pain in patients have been evaluated and are suitable for routine use. A multimodal approach to the treatment of pain should be employed, including pharmacological, surgical, non-pharmacological, and psychological therapies.


2018 ◽  
Vol 18 ◽  
Author(s):  
Artur Karasiński

Word formation in 17th century Gheg AlbanianThe article constitutes a word formation analysis of the Gheg dialect Albanian texts from the 17th century. The only Albanian texts of this period preserved to this day come from northern Albania and form the basis of the so-called old Albanian literature. All their authors came from northern Albania and used a similar variation of the Gheg dialect. The Gheg dialect of Albanian at that time can be considered the standard used by the Catholic environment of Northern Albania. Modern Albanian contains word formations characteristic of both main dialects: Gheg and Tosk. The aim of the present research is to investigate the word-formation structures appearing in 17th century texts. Słowotwórstwo gegijskie XVII wieku Artykuł stanowi analizę słowotwórczą albańskich tekstów z XVII wieku, napisanych w dialekcie gegijskim. Jedyne albańskie teksty tego okresu, zachowane do dziś, pochodzą z północnej Albanii i stanowią podstawę tak zwanej starej literatury albańskiej. Wszyscy autorzy pochodzili z północnej Albanii i używali podobnej odmiany dialektu gegijskiego. Dialekt gegijski może być uznany za standard w tym czasie, używany przez środowisko katolickie w regionie północnej Albanii. Współczesny język albański zawiera formacje słowotwórcze odpowiednie dla obu głównych dialektów gegijskiego i toskijskiego. Badania mają na celu zweryfikowanie struktur słowotwórczych pojawiających się w tekstach z XVII wieku.


2018 ◽  
Author(s):  
Thor Berger ◽  
Per Engzell

A large literature documents how intergenerational mobility—the degree to which (dis)advantage is passed on from parents to children—varies across and within countries. Less is known about the origin or persistence of such differences. We show that U.S. areas populated by descendants to European immigrants have similar levels of income equality and mobility as the countries their forebears came from: highest in areas dominated by descendants to Scandinavian and German immigrants, lower in places with French or Italian heritage, and lower still in areas with British roots. Similar variation in mobility is found for the black population and when analyzing causal place effects, suggesting that mobility differences arise at the community level and extend beyond descendants of European immigrant groups. Our findings indicate that the geography of U.S. opportunity may have deeper historical roots than previously recognized.


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