Antagonistic interactions between predator and prey: mobbing of jaguars (Panthera onca) by white-lipped peccaries (Tayassu pecari)

Abstract Ambush predators rely on stealth to successfully secure prey. Mobbing is a rarely observed anti-predation strategy used by group-living prey species whereby several individuals distract or harass a predator until it either ends the pursuit or leaves the area. Herein, we present three unique cases of white-lipped peccaries (Tayassu pecari) mobbing jaguars (Panthera onca) in the wild. White-lipped peccaries and jaguars co-occur within the study area, a large-scale ecotourism and working cattle ranch in the Brazilian Pantanal. Two cases of mobbing were recorded by video camera trap during routine surveys, and a third case was directly observed by one of the authors during telemetry triangulation of a GPS-collared individual jaguar. Our observations provide direct empirical evidence of antagonistic behavioral interactions between jaguars and white-lipped peccaries that have previously been limited to anecdotes within academic literature. We discuss the implications of this behavioral interaction for the proximate and ultimate fitness of both predator and prey.

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Shape My Face: Registering 3D Face Scans by Surface-to-Surface Translation

International Journal of Computer Vision ◽

10.1007/s11263-021-01494-4 ◽

2021 ◽

Author(s):

Mehdi Bahri ◽

Eimear O’ Sullivan ◽

Shunwang Gong ◽

Feng Liu ◽

Xiaoming Liu ◽

...

Keyword(s):

Large Scale ◽

Training Time ◽

3D Face ◽

In The Wild ◽

Previous State ◽

Surface Translation ◽

Visual Attention Mechanism ◽

Diverse Data ◽

Human Faces ◽

Robust To Noise

AbstractStandard registration algorithms need to be independently applied to each surface to register, following careful pre-processing and hand-tuning. Recently, learning-based approaches have emerged that reduce the registration of new scans to running inference with a previously-trained model. The potential benefits are multifold: inference is typically orders of magnitude faster than solving a new instance of a difficult optimization problem, deep learning models can be made robust to noise and corruption, and the trained model may be re-used for other tasks, e.g. through transfer learning. In this paper, we cast the registration task as a surface-to-surface translation problem, and design a model to reliably capture the latent geometric information directly from raw 3D face scans. We introduce Shape-My-Face (SMF), a powerful encoder-decoder architecture based on an improved point cloud encoder, a novel visual attention mechanism, graph convolutional decoders with skip connections, and a specialized mouth model that we smoothly integrate with the mesh convolutions. Compared to the previous state-of-the-art learning algorithms for non-rigid registration of face scans, SMF only requires the raw data to be rigidly aligned (with scaling) with a pre-defined face template. Additionally, our model provides topologically-sound meshes with minimal supervision, offers faster training time, has orders of magnitude fewer trainable parameters, is more robust to noise, and can generalize to previously unseen datasets. We extensively evaluate the quality of our registrations on diverse data. We demonstrate the robustness and generalizability of our model with in-the-wild face scans across different modalities, sensor types, and resolutions. Finally, we show that, by learning to register scans, SMF produces a hybrid linear and non-linear morphable model. Manipulation of the latent space of SMF allows for shape generation, and morphing applications such as expression transfer in-the-wild. We train SMF on a dataset of human faces comprising 9 large-scale databases on commodity hardware.

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Uyghurs

Chinese Studies ◽

10.1093/obo/9780199920082-0187 ◽

2021 ◽

Author(s):

David O'Brien

Keyword(s):

Ethnic Group ◽

Cultural History ◽

Communist Party ◽

Large Scale ◽

Minority Groups ◽

Group Living ◽

The United States ◽

Early Years ◽

Chinese Government ◽

Complete Control

The Uyghur (alternatively spelled Uighur) are the largest and titular ethnic group living in the Xinjiang Uyghur Autonomous Region, a vast area in northwestern China of over 1.6 million sq. km. According to the 2010 census Uyghurs make up 45.21 percent of the population of Xinjiang, numbering 8,345,622 people. The Han, the largest ethnic group in China, make up 40.58 percent in the region with 7,489,919. A Turkic-speaking largely Muslim ethnic group, the Uyghurs traditionally inhabited a series of oases around the Taklamakan desert. Their complex origin is evidenced by a rich cultural history that can be traced back to various groups that emerged across the steppes of Mongolia and Central Asia. Uyghur communities are also found in Uzbekistan, Kyrgyzstan, and Kazakhstan, with significant diaspora groups in Australia, the United States, Germany, and Turkey. In the first half of the 20th century, Uyghurs briefly declared two short-lived East Turkestan Republics in 1933 and again in 1944, but the region was brought under the complete control of the Chinese state after the Communist Party (CCP) came to power in 1949. Within China they are considered one of the fifty-five officially recognized ethnic minority groups, who, along with the Han who constitute 92 percent of the population, make up the Chinese nation or Zhonghua Minzu中华民族. However, for many Uyghurs the name “Xinjiang,” which literally translates as “New Territory,” indicates that their homeland is a colony of China, and they prefer the term “East Turkestan.” Nevertheless, many scholars use Xinjiang as a natural term even when they are critical of the position of the Communist Party. In this article both terms are used. In the early years of the People’s Republic of China (PRC) Uyghurs numbered about 80 percent of the population of Xinjiang, but large-scale government-sponsored migration has seen the number of Han in the region rise to almost the same as that of the Uyghur. This has led to an increase in ethnic tensions often caused by competition for scarce resources and a perception that the ruling Communist Party favors the Han. In 2009, a major outbreak of violence in the capital Ürümchi saw hundreds die and many more imprisoned. The years 2013 and 2014 were also crucial turning points with deadly attacks on passengers in train stations in Kunming and Yunnan, bombings in Ürümchi, and a suicide attack in Tiananmen Square in Beijing, all blamed on Uyghur terrorists. Since then the Chinese government has introduced a harsh regime of security clampdowns and mass surveillance, which has significantly increased from 2017 and which, by some accounts, has seen over one million Uyghurs and other Muslim ethnic minorities imprisoned without trial in “reeducation” camps. The Chinese government insist these camps form part of an education and vocational training program designed to improve the lives of Uyghurs and root out “wrong thinking.” Many Uyghurs believe it is part of a long-term project of assimilation of Uyghur identity and culture.

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TrackingNet: A Large-Scale Dataset and Benchmark for Object Tracking in the Wild

Computer Vision – ECCV 2018 - Lecture Notes in Computer Science ◽

10.1007/978-3-030-01246-5_19 ◽

2018 ◽

pp. 310-327 ◽

Cited By ~ 45

Author(s):

Matthias Müller ◽

Adel Bibi ◽

Silvio Giancola ◽

Salman Alsubaihi ◽

Bernard Ghanem

Keyword(s):

Object Tracking ◽

Large Scale ◽

Large Scale Dataset ◽

In The Wild

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Fuerza de mordedura y estrés mandibular en el jaguar (Panthera onca) durante la depredación de pecaríes (Artiodactyla: Tayassuidae) mediante la fractura de sus cráneos

ACTA ZOOLÓGICA MEXICANA (N S ) ◽

10.21829/azm.2011.273779 ◽

2011 ◽

Vol 27 (3) ◽

Author(s):

J. Fernando Del Moral Sachetti ◽

Fátima I. Lameda Camacaro ◽

Jorge Santiago Vázquez ◽

Ramiro Zenteno Cárdenas

Keyword(s):

Panthera Onca ◽

Tayassu Pecari

Una de las formas de depredación más efectivas del jaguar (Panthera onca) consiste en la aplicación de su fuerza de mordedura en el neurocráneo de los pecaríes, una de sus principales presas naturales, provocándole un estrés altamente compresivo que deviene en la posterior fractura del cráneo con una muerte rápida. En el presente estudio se analizaron mediante el método del cráneo seco, 15 cráneos completos y medidas craneométricas reportadas en la literatura, para jaguares adultos pertenecientes a diferentes subespecies o fenotipos del rango distributivo de P. onca. Afín de obtener sus fuerzas de mordedura canina y carnasial, esfuerzos de corte y momentos flexores máximos a lo largo del vano mandibular.La obtención de estas variables, en una estructura hiperestática se efectúo mediante el Método de Aproximaciones Sucesivas de Cross. Después se correlacionaron las fuerzas de mordedura máximas del jaguar y su acción en la sección transversal del neurocráneo de ecari tajacu, Tayassu pecari y Catagonus wagneri mediante el método de Cremona, para obtener las tensiones internas que someten al cráneo de los pecaríes previa fractura. Se encontró que la fuerza máxima de mordedura canina del jaguar es de 681,56 Newton siendo 3 veces más compresiva en los carnasiales. Estas son lo suficientementealtas, como para provocar la rotura de una estructura rígida, como la sección triangular del neurocráneo en los pecaríes. Además los caninos robustos del jaguar resisten las fuerzas de pandeo aplicadas sobre los mismos durante la lucha con la presa, y una boca más amplia ayuda a una mejor adherencia y distribución uniforme de las fuerzas de mordedura, durante la mordida mortal.

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Mutations affecting development of the zebrafish inner ear and lateral line

Development ◽

10.1242/dev.123.1.241 ◽

1996 ◽

Vol 123 (1) ◽

pp. 241-254 ◽

Cited By ~ 33

Author(s):

T.T. Whitfield ◽

M. Granato ◽

F.J. van Eeden ◽

U. Schach ◽

M. Brand ◽

...

Keyword(s):

Inner Ear ◽

Lateral Line ◽

Large Scale ◽

Sensory System ◽

Semicircular Canals ◽

Abnormal Development ◽

Pigment Cells ◽

Otic Vesicle ◽

In The Wild ◽

Complementation Groups

Mutations giving rise to anatomical defects in the inner ear have been isolated in a large scale screen for mutations causing visible abnormalities in the zebrafish embryo (Haffter, P., Granato, M., Brand, M. et al. (1996) Development 123, 1–36). 58 mutants have been classified as having a primary ear phenotype; these fall into several phenotypic classes, affecting presence or size of the otoliths, size and shape of the otic vesicle and formation of the semicircular canals, and define at least 20 complementation groups. Mutations in seven genes cause loss of one or both otoliths, but do not appear to affect development of other structures within the ear. Mutations in seven genes affect morphology and patterning of the inner ear epithelium, including formation of the semicircular canals and, in some, development of sensory patches (maculae and cristae). Within this class, dog-eared mutants show abnormal development of semicircular canals and lack cristae within the ear, while in van gogh, semicircular canals fail to form altogether, resulting in a tiny otic vesicle containing a single sensory patch. Both these mutants show defects in the expression of homeobox genes within the otic vesicle. In a further class of mutants, ear size is affected while patterning appears to be relatively normal; mutations in three genes cause expansion of the otic vesicle, while in little ears and microtic, the ear is abnormally small, but still contains all five sensory patches, as in the wild type. Many of the ear and otolith mutants show an expected behavioural phenotype: embryos fail to balance correctly, and may swim on their sides, upside down, or in circles. Several mutants with similar balance defects have also been isolated that have no obvious structural ear defect, but that may include mutants with vestibular dysfunction of the inner ear (Granato, M., van Eeden, F. J. M., Schach, U. et al. (1996) Development, 123, 399–413,). Mutations in 19 genes causing primary defects in other structures also show an ear defect. In particular, ear phenotypes are often found in conjunction with defects of neural crest derivatives (pigment cells and/or cartilaginous elements of the jaw). At least one mutant, dog-eared, shows defects in both the ear and another placodally derived sensory system, the lateral line, while hypersensitive mutants have additional trunk lateral line organs.

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Opportunistic or Non-Random Wildlife Crime? Attractiveness Rather Than Abundance in the Wild Leads to Selective Parrot Poaching

Diversity ◽

10.3390/d12080314 ◽

2020 ◽

Vol 12 (8) ◽

pp. 314 ◽

Cited By ~ 4

Author(s):

Pedro Romero-Vidal ◽

Fernando Hiraldo ◽

Federica Rosseto ◽

Guillermo Blanco ◽

Martina Carrete ◽

...

Keyword(s):

Large Scale ◽

Methodological Approach ◽

Wildlife Trade ◽

High Demand ◽

Wildlife Crime ◽

Conservation Implications ◽

Species Abundances ◽

In The Wild ◽

Large Scale Survey ◽

First Time

Illegal wildlife trade, which mostly focuses on high-demand species, constitutes a major threat to biodiversity. However, whether poaching is an opportunistic crime within high-demand taxa such as parrots (i.e., harvesting proportional to species availability in the wild), or is selectively focused on particular, more desirable species, is still under debate. Answering this question has important conservation implications because selective poaching can lead to the extinction of some species through overharvesting. However, the challenges of estimating species abundances in the wild have hampered studies on this subject. We conducted a large-scale survey in Colombia to simultaneously estimate the relative abundance of wild parrots through roadside surveys (recording 10,811 individuals from 25 species across 2221 km surveyed) and as household, illegally trapped pets in 282 sampled villages (1179 individuals from 21 species). We used for the first time a selectivity index to test selection on poaching. Results demonstrated that poaching is not opportunistic, but positively selects species based on their attractiveness, defined as a function of species size, coloration, and ability to talk, which is also reflected in their local prices. Our methodological approach, which shows how selection increases the conservation impacts of poaching for parrots, can be applied to other taxa also impacted by harvesting for trade or other purposes.

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The ontogeny of a mammalian cognitive map in the real world

Science ◽

10.1126/science.aay3354 ◽

2020 ◽

Vol 369 (6500) ◽

pp. 194-197 ◽

Cited By ~ 5

Author(s):

Lee Harten ◽

Amitay Katz ◽

Aya Goldshtein ◽

Michal Handel ◽

Yossi Yovel

Keyword(s):

Real World ◽

Large Scale ◽

Cognitive Maps ◽

Cognitive Map ◽

Interindividual Differences ◽

The Real ◽

Fruit Bat ◽

Wild Fruit ◽

In The Wild

How animals navigate over large-scale environments remains a riddle. Specifically, it is debated whether animals have cognitive maps. The hallmark of map-based navigation is the ability to perform shortcuts, i.e., to move in direct but novel routes. When tracking an animal in the wild, it is extremely difficult to determine whether a movement is truly novel because the animal’s past movement is unknown. We overcame this difficulty by continuously tracking wild fruit bat pups from their very first flight outdoors and over the first months of their lives. Bats performed truly original shortcuts, supporting the hypothesis that they can perform large-scale map-based navigation. We documented how young pups developed their visual-based map, exemplifying the importance of exploration and demonstrating interindividual differences.

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Comparative Analysis of Supervised and Unsupervised Approaches Applied to Large-Scale “In The Wild” Face Verification

Symmetry ◽

10.3390/sym12111832 ◽

2020 ◽

Vol 12 (11) ◽

pp. 1832

Author(s):

Tomasz Hachaj ◽

Patryk Mazurek

Keyword(s):

Pattern Recognition ◽

Large Scale ◽

Statistical Significance ◽

Ground Truth ◽

Classification Algorithm ◽

Adjusted Rand Index ◽

Face Verification ◽

Data Set ◽

In The Wild ◽

Unsupervised Approaches

Deep learning-based feature extraction methods and transfer learning have become common approaches in the field of pattern recognition. Deep convolutional neural networks trained using tripled-based loss functions allow for the generation of face embeddings, which can be directly applied to face verification and clustering. Knowledge about the ground truth of face identities might improve the effectiveness of the final classification algorithm; however, it is also possible to use ground truth clusters previously discovered using an unsupervised approach. The aim of this paper is to evaluate the potential improvement of classification results of state-of-the-art supervised classification methods trained with and without ground truth knowledge. In this study, we use two sufficiently large data sets containing more than 200,000 “taken in the wild” images, each with various resolutions, visual quality, and face poses which, in our opinion, guarantee the statistical significance of the results. We examine several clustering and supervised pattern recognition algorithms and find that knowledge about the ground truth has a very small influence on the Fowlkes–Mallows score (FMS) of the classification algorithm. In the case of the classification algorithm that obtained the highest accuracy in our experiment, the FMS improved by only 5.3% (from 0.749 to 0.791) in the first data set and by 6.6% (from 0.652 to 0.718) in the second data set. Our results show that, beside highly secure systems in which face verification is a key component, face identities discovered by unsupervised approaches can be safely used for training supervised classifiers. We also found that the Silhouette Coefficient (SC) of unsupervised clustering is positively correlated with the Adjusted Rand Index, V-measure score, and Fowlkes–Mallows score and, so, we can use the SC as an indicator of clustering performance when the ground truth of face identities is not known. All of these conclusions are important findings for large-scale face verification problems. The reason for this is the fact that skipping the verification of people’s identities before supervised training saves a lot of time and resources.

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Occupancy estimation of jaguar Panthera onca to assess the value of east-central Mexico as a jaguar corridor

Oryx ◽

10.1017/s0030605313000069 ◽

2013 ◽

Vol 48 (1) ◽

pp. 133-140 ◽

Cited By ~ 16

Author(s):

Lisanne S. Petracca ◽

O. Eric Ramírez-Bravo ◽

Lorna Hernández-Santín

Keyword(s):

Large Scale ◽

Prey Species ◽

Landscape Connectivity ◽

Site Occupancy ◽

Sampling Unit ◽

Eastern Coast ◽

Panthera Onca ◽

Occupancy Modelling ◽

Pecari Tajacu ◽

Collared Peccary

AbstractThe use of wildlife corridors to maintain landscape connectivity has become increasingly relevant to the conservation of wide-ranging species, including the jaguar Panthera onca. Jaguars are particularly threatened in Mexico, where corridor linkages are tenuous as a result of habitat fragmentation. Our study assessed a section of potential corridor south of the Sierra Madre Oriental in eastern Mexico. We conducted 245 interviews with local inhabitants in 140 36-km2 sampling units over a 5-month period and compiled detection histories for jaguars and five prey species: collared peccary Pecari tajacu, red brocket deer Mazama americana, white-tailed deer Odocoileus virginianus, spotted paca Agouti paca, and nine-banded armadillo Dasypus novemcinctus. These detection histories were then analysed using site occupancy modelling. Each sampling unit was assigned a probability of habitat use based on (1) the two smaller prey species (paca and armadillo) and (2) at least two of the larger prey species (collared peccary and two deer species) using habitat in that unit. This probability estimate was considered a proxy for the prey base of each sampling unit and therefore the unit's suitability as a jaguar corridor. Although the prey base in some areas appears adequate to support a jaguar population, large-scale development projects and the paucity of jaguar sign are major obstacles to this region's potential as a jaguar corridor. Our results suggest that the eastern coast of Mexico may not be a priority area for range-wide jaguar conservation.

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