scholarly journals Seed ingestion and germination in rattlesnakes: overlooked agents of rescue and secondary dispersal

2018 ◽  
Vol 285 (1872) ◽  
pp. 20172755 ◽  
Author(s):  
Randall S. Reiserer ◽  
Gordon W. Schuett ◽  
Harry W. Greene
Keyword(s):  
Seed Dispersal ◽  
Population Ecology ◽  
Empirical Studies ◽  
Evolutionary Process ◽  
Terrestrial Plants ◽  
Frugivorous Birds ◽  
Secondary Dispersal ◽  
Cheek Pouches ◽  
Primary Dispersal

Seed dispersal is a key evolutionary process and a central theme in the population ecology of terrestrial plants. The primary producers of most land-based ecosystems are propagated by and maintained through various mechanisms of seed dispersal that involve both abiotic and biotic modes of transportation. By far the most common biotic seed transport mechanism is zoochory, whereby seeds, or fruits containing them, are dispersed through the activities of animals. Rodents are one group of mammals that commonly prey on seeds (granivores) and play a critical, often destructive, role in primary dispersal and the dynamics of plant communities. In North America, geomyid, heteromyid and some sciurid rodents have specialized cheek pouches for transporting seeds from plant source to larder, where they are often eliminated from the pool of plant propagules by consumption. These seed-laden rodents are commonly consumed by snakes as they forage, but unlike raptors, coyotes, bobcats, and other endothermic predators which eat rodents and are known or implicated to be secondary seed dispersers, the role of snakes in seed dispersal remains unexplored. Here, using museum-preserved specimens, we show that in nature three desert-dwelling rattlesnake species consumed heteromyids with seeds in their cheek pouches. By examining the entire gut we discovered, furthermore, that secondarily ingested seeds can germinate in rattlesnake colons. In terms of secondary dispersal, rattlesnakes are best described as diplochorous. Because seed rescue and secondary dispersal in snakes has yet to be investigated, and because numerous other snake species consume granivorous and frugivorous birds and mammals, our observations offer direction for further empirical studies of this unusual but potentially important channel for seed dispersal.

scholarly journals Role of species: traits, interactions and ecosystem services

2018 ◽  
Vol 2 ◽  
pp. e25345
Author(s):  
Tereza Giannini ◽  
Marcelo Awade ◽  
Leonardo Miranda ◽  
Leonardo Trevelin ◽  
Carlos Silva ◽  
...  
Keyword(s):  
Ecosystem Services ◽  
Seed Dispersal ◽  
Functional Traits ◽  
Evolutionary History ◽  
Pollen Grains ◽  
Species Traits ◽  
The Body ◽  
Frugivorous Birds ◽  
Basic Premise

Understanding the role that species play in their environment is a fundamental goal of biodiversity research, bringing knowledge on ecosystem maintenance and in provision of ecosystem services. Different types of interaction that different species establish with their partners regulate the functioning of ecosystems (McCann 2007). Interactions between plants and pollinators (Potts et al. 2016) and between plants and seed dispersers (Wang and Smith 2002) are examples of mutualism, crucial to the maintenance of the floristic composition and overall biodiversity in different biomes. They also illustrate well the nature's contribution to people, supporting ecosystem services with key economic consequences, such as pollination of agricultural crops (Klein et al. 2007) and seed dispersal of natural or assisted restoration of degraded areas (Wunderle 1997). Interactions are mediated by different functional traits (morphological and/or behavioral characteristics of organisms that influence their performance) (Ball et al. 2015). As the zoochorous transfer of pollen grains and seeds usually involves contact, the success of pollination and seed dispersal depends to a large extend on the relationship of size and morphology between flower/fruit and their respective pollinator/seed disperser. Selected over a long history of shared evolutionary history, it is feasible to rely on the predictive potential these traits may have to determine if a certain animal is able to transfer pollen grains and/or seeds of specific plants in the landscape (Howe 2016). Biodiversity is facing constant negative impacts, especially related to climate and habitat changes. They are threatening the provision of ecosystem services, jeopardizing the basic premise of sustainable development, which is to guarantee resources for future generations. The novel landscapes that result from these impacts will certainly be dependent of these ecosystem services, but will they persist in face of extinctions and invasive competitors? Ultimately, will these services be predicable by functional traits, in landscapes where shared evolutionary history is reduced? Strategies that help our understanding of the interactions and their role in the provision of services are urgent (Corlett 2011). Given this context, our objective here is to present the type of data that, if made available, could assist in determining the role of species in terms of the interactions they make and the provision of ecosystem services. Moreover, we aimed to elucidate how this role can be associated with functional traits. The current work focuses on the following groups: plants, birds, bats and bees (Fig. 1). Of particular interest are interactions involving: pollination, which is carried out predominantly by bees, but also by nectarivorous birds and bats; and seed dispersal, mainly carried out by frugivorous birds and bats. These interactions are mediated by key traits. In plants, common flower traits are the aperture, color, odor strength and type, shape orientation, size and symmetry, nectar guide and sexual organ, and reward. Fruit or seed traits, such as fleshy nutrient, chemical attractant and clinging structures, are also relevant for seed dispersal. In animals the most common traits are the body size (for bees, the intertegular distance; for bats, forearm length; and for birds, the weight), gape-width for birds and the feeding habit (nectarivorous, frugivorous, omnivorous) for bats and birds. Providing standardized data on traits involving interactions between fauna and flora is important to fill knowledge gaps, which could help in the decision making processes aiming conservation, restoration and management programs for protecting ecosystem services based on biodiversity.

scholarly journals USE OF RESTORATION PLANTINGS TO ENHANCE BIRD SEED DISPERSAL AT THE ROADSIDE: FAILURES AND PROSPECTS

2015 ◽  
Vol 23 (4) ◽  
pp. 302-311 ◽  
Author(s):  
Rocío de TORRE ◽  
María Dolores JIMÉNEZ ◽  
Álvaro RAMÍREZ ◽  
Ignacio MOLA ◽  
Miguel A. CASADO ◽  
...  
Keyword(s):  
Species Richness ◽  
Seed Dispersal ◽  
Agricultural Landscape ◽  
Bird Species ◽  
Ecological Processes ◽  
Frugivorous Birds ◽  
Bird Droppings ◽  
Bird Richness ◽  
Species Richness And Abundance

Plantings are commonly used in roadside reclamation for ornamental purposes and for increasing slope stability and road safety. However, the role of these plantings in restoring ecological processes, such as seed dispersal, has received little attention. We carried out a study to assess the potential role of plantings on roadside embankments to attract frugivorous birds and to enhance seed dispersal mediated by birds from the surrounding landscape. We examined: (1) bird species richness and abundance; (2) patterns of avian spatial distribution within embankments and (3) seed dispersal mediated by birds. Bird richness and abundance did not differ between embankments with and without plantings. However, birds were not distributed randomly within embankments, with levels of species richness and abundance for facultative frugivorous between 4.8–8 times higher in areas closer to plantings. An analysis of bird droppings showed that birds only dispersed seeds of the planted species since no seeds of woody plants from matrices were detected. These results suggest that plantings acted as selective bird attractors, providing food and perches for frugivorous species. Nevertheless, the scarcity of seed-dispersing birds in the surrounding agricultural landscape prevented plantings from enhancing seed dispersal and connectivity to adjacent habitat.

Dispersal of mimetic seeds of three species of Ormosia (Leguminosae)

1998 ◽  
Vol 14 (4) ◽  
pp. 389-411 ◽  
Author(s):  
Mercedes S. Foster ◽  
Linda S. Delay
Keyword(s):  
Seed Germination ◽  
Seed Dispersal ◽  
Seed Coat ◽  
Seed Predation ◽  
The Other ◽  
Frugivorous Birds ◽  
Hard Seed ◽  
Seed Surface ◽  
Mutualistic Relationship

ABSTRACT. Seeds with ‘imitation arils’ appear wholly or partially covered by pulp or aril but actually carry no fleshy material. The mimetic seed hypothesis to explain this phenomenon proposes a parasitic relationship in which birds are deceived into dispersing seeds that resemble bird-dispersed fruits, without receiving a nutrient reward. The hard-seed for grit hypothesis proposes a mutualistic relationship in which large, terrestrial birds swallow the exceptionally hard mimetic seeds as grit for grinding the softer seeds on which they feed. They defecate, dispersing the seeds, and abrade the seed surface, enhancing germination. Any fruit mimicry is incidental. Fruiting trees of Ormosia spp. (Leguminosae: Papilionoideae) were observed to ascertain mechanisms of seed dispersal and the role of seemingly mimetic characteristics of the seeds in that dispersal. Seed predation and seed germination were also examined. Ormosia isthamensis and O. macrocalyx (but not O. bopiensis) deceived arboreally-foraging frugivorous birds into taking their mimetic seeds, although rates of seed dispersal were low. These results are consistent with the mimetic seed hypothesis. On the other hand, the rates of disappearance of seeds from the ground under the Ormosia trees, hardness of the seeds, and enhancement of germination with the abrasion of the seed coat are all consistent with the hard-seed for grit hypothesis. RESUMEN. Semillas con arilos falsos aparecen estar cubiertas en parte o completamente por pulpa o arilo, pero en realidad no llevan ninguna materia carnosa. El hipótesis semilla mímica propone que las semillas parecen frutos carnosos cuyas semillas están dispersadas por aves y que engañan las aves a dispersar sus semillas sin recibir una recompensa nutritiva — una relación parasítica. El hipótesis semilla dura para arenisca propone que aves grandes y terrestres tragan las semillas mímicas y excepcionalmente duras como arenisca para moler las semillas más suaves en que se alimentan; las aves defecan y dispersan las semillas, y las rascan, lo cual mejora la germinación — una relación mutua. Cualquier mimetismo es incidente. Se observaron árboles de Ormosia espp. (Leguminosae: Papilionoideae) con frutos para averiguar los mecanismos de dispersión de semillas y el papel que hacen las características aparentemente mímicas de sus semillas en esa dispersión. Se examinaron también la depredación y germinación de semillas. Las semillas mímicas de Ormosia isthamensis y O. macrocalyx (pero no O. bopiensis), engañaron aves frugivoras y arbóreas en comerlas, aunque las tasas de dispersión eran bajas. Estos resultados son consistente con el hipótesis semilla mímica. En cambio, las tasas de desaparición de semillas caídas de Ormosia, dureza de las semillas, y mejoramiento de germinación con la raedura de las capas de las semillas son consistente con el hipótesis semilla dura para arenisca.

scholarly journals Potential role of frugivorous birds (Passeriformes) on seed dispersal of six plant species a restinga habitat, southeastern Brazil

2006 ◽  
Vol 56 (1) ◽  
Author(s):  
Verónica Souza da Mota Gomes ◽  
Maria Célia Rodrigues Correia ◽  
Heloisa Alves de Lima ◽  
Maria Alice S. Alves
Keyword(s):  
Seed Dispersal ◽  
Plant Species ◽  
Potential Role ◽  
Southeastern Brazil ◽  
Frugivorous Birds

scholarly journals The role of avian frugivores on germination and potential seed dispersal of the Brazilian Pepper Schinus terebinthifolius

2010 ◽  
Vol 10 (3) ◽  
pp. 45-51 ◽  
Author(s):  
Graziele D'Avila ◽  
Antonio Gomes-Jr ◽  
Ana Carolina Canary ◽  
Leandro Bugoni
Keyword(s):  
Seed Dispersal ◽  
Seed Viability ◽  
Bird Species ◽  
Frugivorous Birds ◽  
Schinus Terebinthifolius ◽  
In Captivity ◽  
Avian Frugivores ◽  
Brazilian Pepper ◽  
Germination Experiments

Frugivorous birds play a key role in seed dispersal and establishment of a range of plant species, including invasive weeds, such as the Brazilian Pepper Schinus terebinthifolius. The potential of seed dispersal of Schinus by birds with varied feeding behaviours was studied through seed-viability tests and germination experiments using seeds obtained from birds in the field and birds kept in captivity. It was found that seeds collected after gut passage in five bird species in the field had higher proportion of germination as well as higher germination rates compared to the control seeds. Viability of seeds ingested by the Blue-and-yellow Tanager Thraupis bonariensis, which mandibulates seeds before ingesting, was significantly lower than control seeds, while reduction in viability of seeds ingested by the Creamy-bellied Thrush Turdus amaurochalinus was nonsignificant. Seeds ingested by birds in captivity germinated earlier than the control seeds, within 1-2 weeks, and had proportion and germination rates higher than controls. Probably both mechanical and chemical effects play a role in enhancing germination of seeds. In Brazil where both Schinus and avian frugivores had evolved together, the dependence of Schinus on generalist frugivores had been demonstrated in this study, similar to other countries where the invasive Schinus is dependent on native or introduced avian species for its spreading. This finding has important implications for the restoration of human-altered areas in South America, were Schinus is a native pioneer species, as well as for the management and restoration of areas invaded by Schinus elsewhere.

On the role of conflict in the evolutionary process

2016 ◽  
pp. 87-91
Author(s):  
V.I. Bol’shakov ◽  
◽  
Yu.I. Dubrov ◽  
Keyword(s):  
Evolutionary Process

Mathematics Textbook as an Object of Research/Matematički udžbenik kao predmet istraživanja

2014 ◽  
Vol 16 ◽  
Author(s):  
Dubravka Glasnović Gracin
Keyword(s):  
Mathematics Education ◽  
Mathematical Knowledge ◽  
Empirical Studies ◽  
Mathematics Textbooks ◽  
Mathematics Textbook ◽  
Mathematics Book

AbstractA mathematics textbook can be described as an officially authorized and pedagogically designed mathematics book written to provide mathematical knowledge to students. This description suggests the authority of the textbook - because it has been authorized by an administrative source and because it deals with authorized knowledge. This paper provides an overview of research on mathematics textbooks. The emphasis is on questions concerning the extent to which and how textbooks are used in mathematics education in Croatia and in the world.Research results show that mathematics textbooks are widely used in mathematics education worldwide. This finding points to the need for research on the content and structure of textbooks. Such studies are combined with the associated results on how textbooks are used in the classroom and which methods teachers apply in using textbooks in mathematics education. The results of the empirical studies show that teachers use textbooks for lesson preparation and pupils use mathematics textbooks for exercises to a great extent. These results imply that such an important role of textbooks in mathematics education deserves additional attention, with the goal of understanding and improving mathematics education.Key words: mathematics education; overview; research on textbook---SažetakMatematički udžbenik može se opisati kao službeno autorizirana i pedagoki osmiljena matematička knjiga napisana s ciljem da učenicima ponudi matematičke sadržaje. Taj opis sugerira autoritet udžbenika jer ga je autorizirao administrativni izvor i jer sadrži autorizirano znanje. Ovaj članak daje pregled istraživanja matematičkih udžbenika, a naglasak je na pitanjima u kojoj mjeri i kako se udžbenici koriste u nastavi matematike u Hrvatskoj i u svijetu.Rezultati raznih istraživanja pokazuju da se udžbenici u velikoj mjeri koriste u nastavi matematike irom svijeta. Taj nalaz ukazuje na potrebu za istraživanjem sadržaja i strukture matematičkih udžbenika. Uz to, prikazani su rezultati istraživanja o tome na koji se način udžbenici koriste u razredu i koje metode nastavnici prakticiraju prilikom upotrebe udžbenika na nastavi. Rezultati empirijskih studija pokazuju da nastavnici udžbenike većinom koriste za pripremu nastavnog sata, a učenici udžbenike koriste u najvećoj mjeri za vježbanje. Ti rezultati ukazuju na to da tako važna uloga udžbenika u matematičkom obrazovanju zaslužuje dodatnu pažnju s ciljem razumijevanja i poboljanja nastave matematike.Ključne riječi: istraživanje udžbenika; nastava matematike; pregled.

The Role of Theories of Embodied Cognition in Research and Modeling of Emotions

2019 ◽  
Vol 62 (5) ◽  
pp. 124-138
Author(s):  
Alexandra V. Shiller
Keyword(s):  
Artificial Intelligence ◽  
Embodied Cognition ◽  
Mirror Neurons ◽  
Empirical Studies ◽  
Unknown Quantity ◽  
Emotional Processes ◽  
Strong Artificial Intelligence ◽  
European Philosophy ◽  
Postmodern Philosophy

The article analyzes the role of theories of embodied cognition for the development of emotion research. The role and position of emotions changed as philosophy developed. In classical and modern European philosophy, the idea of the “primacy of reason” prevailed over emotions and physicality, emotions and affective life were described as low-ranking phenomena regarding cognitive processes or were completely eliminated as an unknown quantity. In postmodern philosophy, attention focuses on physicality and sensuality, which are rated higher than rational principle, mind and intelligence. Within the framework of this approach, there is a recently emerged theory of embodied cognition, which allows to take a fresh look at the place of emotions in the architecture of mental processes – thinking, perception, memory, imagination, speech. The article describes and analyzes a number of empirical studies showing the impossibility of excluding emotional processes and the significance of their research for understanding the architecture of embodied cognition. However, the features of the architecture of embodied cognition remain unclear, and some of the discoveries of recent years (mirror neurons or neurons of simulation) rather raise new questions and require further research. The rigorously described and clear architecture of the embodied cognition can grow the theoretical basis that will allow to advance the studies of learning processes, language understanding, psychotherapy techniques, social attitudes and stereotypes, highlight the riddle of consciousness and create new theories of consciousness or even create an anthropomorphic artificial intelligence that is close to “strong artificial intelligence.”

Expectations from Chinese Muslim Converts for Islamization of Society in Malaysia: Lessons from Life of the Companions (Angkaan Pengubahsuaian Cina Islam untuk Pengislaman Soci-ety di Malaysia: Pelajaran dari Kehidupan Para Sahabat)

2019 ◽  
Vol 16 (1) ◽  
pp. 278-296
Author(s):  
Mek Wok Mahmud ◽  
Sayed Sikandar Shah Haneef
Keyword(s):  
Economic Development ◽  
Empirical Studies ◽  
The Self ◽  
Way Of Life ◽  
Socio Economic Development ◽  
Chinese Muslims ◽  
Process Studies ◽  
Divine Guidance

Reversion to Islam while opening golden opportunities for a revert in terms of divine guidance and spiritual salvation is coming with somewhat insurmountable challenges in terms of Islamization of the self, family and contributions to the overall development of Malaysia as a multi-religious country. This is especially so when Islam as an official religion has made the issue of Islamization of the Malaysian society and its systems amongst the pivotal national agendas in the country.  As to what is the role of Chinese Muslims (reverts) in the process, studies, among others, have purported to present the statistics about their share in socio-economic development. Similarly, empirical studies point to the odds faced by this community at personal, family and community levels in their path for transition to the full Islamic way of life. To the presenters of this paper, however, the macro dimension of what it means to become a Muslim which is essential for adjustment to the Islamic requirements has not been sufficiently highlighted in discourses in the area. Accordingly, this paper presents the position statements on Islamic expectations from Chinese reverts with the purpose of motivating them to achieve greater things in the area of Islamization of their community and the nation to the effect. Keywords: Chinese converts, Islamization, expectations and challenges. Abstrak kembalinya seseorang kepada agama Islam selain dari membuka peluang keemasan dalam mendapat  petunjuk Ilahi dan pengisian rohani turut disertai dengan cabaran yang amat sukar untuk diatasi termasuklah cabaran Islamisasi diri, keluarga serta sumbangan kepada pembangunan keseluruhan Malaysia sebagai negara berbilang agama. Hal ini menjadi satu keutamaan terutamanya apabila Islam memegang status sebagai agama rasmi persekutuan yang menjadikan isu Islamisasi masyarakat Malaysia sebagai satu agenda nasional. Bagi menjayakan agenda ini, peranan umat Islam dari kalangan masyarakat Cina (cina muslim) juga perlu diambil kira. Statistik menunjukkan cina muslim turut mempunyai bahagian dalam menyumbang terhadap pembangunan sosio-ekonomi negara. Dalam pada masa yang sama, kajian empirikal membuktikan adanya bentuk bentuk cabaran yang dihadapi oleh komuniti ini di peringkat peribadi, keluarga dan komuniti dalam perjalanan mereka untuk kembali kepada cara hidup Islam yang sepenuhnya. Bagi kami pengkaji kertas ini, dimensi makro dalam menjadikan dan mengertikan  seseorang itu Muslim terutamanya dalam menyesuaikan diri dengan ajaran  Islam masih belum cukup diberi  penjelasan dan penerangan yang sewajarnya. Oleh itu, makalah ini cuba menerangkan idea dan cadangan yang berguna kepada cina muslim dengan tujuan memotivasikan  mereka bagi  mencapai kejayaan  yang lebih besar dari aspek Islamisasi di kalangan komuniti mereka seterusnya memberi sumbangan kepada negara. Kata kunci:  Cina Muslim, Islamisasi, harapan dan cabaran.

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