Bands of brothers and in-laws: Waorani warfare, marriage and alliance formation

The root of modern human warfare lies in the lethal coalitionary violence of males in small-scale societies. However, there is a paucity of quantitative data concerning the form and function of coalitionary violence in this setting. Debates exist over how lethal coalitions are constituted, as well as the motivations and benefits for males to join such groups. Data from a lowland Amazonian population, the Waorani of Ecuador, illuminate three issues: (i) the degree to which raiding parties are composed of groups of fraternal kin as opposed to strategic alliances of actual or potential affinal kin; (ii) the extent to which individuals use pre-existing affinal ties to motivate others to participate in war or leverage warfare as a mechanism to create such ties; and (iii) the extent to which participation in raiding is driven by rewards associated with future marriage opportunities. Analyses demonstrate that Waorani raiding parties were composed of a mix of males who were potential affines, actual affines and fraternal kin, suggesting that men used pre-existing genetic, lineal and social kin ties for recruiting raid partners and used raiding as a venue to create novel social relationships. Furthermore, analyses demonstrate that males leveraged raiding alliances to achieve marriage opportunities for themselves as well as for their children. Overall, it appears that a complex set of motivations involving individual rewards, kin marriage opportunities, subtle coercion and the assessment of alliance strength promote violent intergroup conflict among the Waorani. These findings illustrate the complex inter-relationships among kin selection, coalition building and mating success in our species.

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As-Built Geometry and Surface Finish Effects on Fatigue and Tensile Properties of Laser Fused Titanium 6Al-4V

Volume 6: Ceramics; Controls, Diagnostics and Instrumentation; Education; Manufacturing Materials and Metallurgy ◽

10.1115/gt2017-63482 ◽

2017 ◽

Cited By ~ 2

Author(s):

Onome Scott-Emuakpor ◽

Tommy George ◽

Emily Henry ◽

Casey Holycross ◽

Jeff Brown

Keyword(s):

Tensile Properties ◽

Surface Finish ◽

Fatigue Behavior ◽

Turbine Blades ◽

Material Behavior ◽

Small Scale ◽

Internal Cooling ◽

Roughness Effects ◽

Form And Function ◽

And Function

The as-built material behavior of additive manufactured (AM) Titanium (Ti) 6Al-4V is investigated in this study. A solution heat treated, aged, stress relieved, and hot isostatic pressed Laser Powder Bed Fusion (LPBF) AM process was used to manufacture the specimens of interest. The motivation behind this work is based on the ever-growing desire of aerospace system designers to use AM to fabricate components with novel geometries. Specifically, there is keen interest in AM components with complex internal cooling configurations such as turbine blades, nozzle vanes, and heat exchangers that can improve small scale propulsion performance. Though it is feasible to three-dimensionally print parts that meet the Fit portion of a part characteristic description and identification, the Form and Function portions have proven to be more difficult to conquer. This study addresses both the Form and Function characteristics of the LPBF AM process via the investigation of geometry variation and surface roughness effects pertaining to mechanical properties and fatigue behavior of Ti 6Al-4V. Results show that geometry variation may be the cause of increased vibration fatigue life uncertainty. Also, both fatigue and tensile properties show profound discrepancies associated with surface finish. As-built surface finish specimens have lower fatigue and ductility performance, but the results are more consistent than polished data.

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How to chat in English and Chinese: Emerging digital language conventions

ReCALL ◽

10.1017/s0958344004000527 ◽

2004 ◽

Vol 16 (2) ◽

pp. 308-329 ◽

Cited By ~ 17

Author(s):

HEATHER LOTHERINGTON ◽

YEJUN XU

Keyword(s):

Online Communication ◽

Language Instruction ◽

Small Scale ◽

Factors Affecting ◽

Second Languages ◽

Form And Function ◽

World Languages ◽

Teachers And Students ◽

Digital Environments ◽

And Function

Rapid changes in language form and function occurring in digital environments present teachers and students of second languages alike with conundrums as to language and discourse standards. Factors affecting the changes that are emerging in digital English include the spatial and temporal possibilities and constraints of the medium, digital facilitation of case-creativity and iconic incorporation, and new social network configurations. This paper analyzes evolving changes in orthographic, syntactic, discourse and sociocultural conventions occurring in English and Chinese in digital environments, based on a small scale study conducted at York University in 2002–2003, noting trends across these languages as well as more limited, culturally and linguistically specific evolutions. The converging conventional changes occurring in these two major world languages suggest that similar transitions are happening generally in languages used for online communication, which has serious implications for second language instruction.

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Understanding Virtual Objects through Reverse Engineering

Virtual Archaeology Review ◽

10.4995/var.2012.4372 ◽

2012 ◽

Vol 3 (7) ◽

pp. 14 ◽

Cited By ~ 1

Author(s):

Vera Moitinho ◽

Juan Anton Barceló

Keyword(s):

Reverse Engineering ◽

Quantitative Data ◽

Social Activity ◽

Archaeological Record ◽

Input Output ◽

Virtual Objects ◽

Form And Function ◽

Quantitative Data Analysis ◽

And Function ◽

The Relationship

<p>The main objective of our research is to develop a new methodology, based on Reverse Engineering processes – 3D scan, quantitative data analysis and Artificial Intelligence techniques, in particular simulation – to study the relationship between form and function of artefacts. Furthermore, we aim to provide new data, as well as possible explanations of the archaeological record according to what it expects about social activity, including working processes, by simulating the potentialities of such actions in terms of input-output relationships.</p>

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Reasons to strike first

Behavioral and Brain Sciences ◽

10.1017/s0140525x19000840 ◽

2019 ◽

Vol 42 ◽

Author(s):

William Buckner ◽

Luke Glowacki

Keyword(s):

Intergroup Conflict ◽

Small Scale

Abstract De Dreu and Gross predict that attackers will have more difficulty winning conflicts than defenders. As their analysis is presumed to capture the dynamics of decentralized conflict, we consider how their framework compares with ethnographic evidence from small-scale societies, as well as chimpanzee patterns of intergroup conflict. In these contexts, attackers have significantly more success in conflict than predicted by De Dreu and Gross's model. We discuss the possible reasons for this disparity.

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Scanning tunneling microscopy (STM) of DNA and RNA

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100152148 ◽

1989 ◽

Vol 47 ◽

pp. 34-35

Author(s):

Patricia G. Arscott ◽

Gil Lee ◽

Victor A. Bloomfield ◽

D. Fennell Evans

Keyword(s):

Molecular Structures ◽

Inorganic Materials ◽

Resolving Power ◽

Scanning Tunneling ◽

Tunneling Microscopy ◽

Form And Function ◽

Dna And Rna ◽

Calf Thymus ◽

And Function ◽

The Relationship

STM is one of the most promising techniques available for visualizing the fine details of biomolecular structure. It has been used to map the surface topography of inorganic materials in atomic dimensions, and thus has the resolving power not only to determine the conformation of small molecules but to distinguish site-specific features within a molecule. That level of detail is of critical importance in understanding the relationship between form and function in biological systems. The size, shape, and accessibility of molecular structures can be determined much more accurately by STM than by electron microscopy since no staining, shadowing or labeling with heavy metals is required, and there is no exposure to damaging radiation by electrons. Crystallography and most other physical techniques do not give information about individual molecules.We have obtained striking images of DNA and RNA, using calf thymus DNA and two synthetic polynucleotides, poly(dG-me5dC)·poly(dG-me5dC) and poly(rA)·poly(rU).

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