Convergences and Divergences in Communication and Social-Organization of Desert Rodents

1994 ◽  
Vol 42 (4) ◽  
pp. 405 ◽  
Author(s):  
JA Randall

Has behaviour of desert rodents evolved to show convergences in the same way as morphological and physiological traits? To answer this question, I compared social behaviour and communication of rodents from deserts in North America, Africa, Eurasia and Australia, Most desert rodents, except those from Australia, sandbathe and footdrum as primary modes of communication. In contrast, social behaviour in desert rodents has evolved across a wide spectrum of sociality. The most highly evolved social organisation in mammals occurs in two species of eusocial mole-rats from arid deserts in Africa, Asian gerbils live in stable family groups, and jerboas in northern Africa may be socially tolerant. The heteromyid rodents from North America, however, live alone in a social structure maintained by neighbour recognition. These communication convergences and social divergences may be explained by the evolutionary history of the rodents and by contrasts in resources, predation and climate. Mole-rats must cooperate to harvest dispersed underground tubers in arid environments. Varied diets and cold climates possibly selected for group living in the highly social gerbils. The long and successful evolution of heteromyid rodents as solitary granivores may explain why they have not taken the next step in social evolution.

2003 ◽  
Vol 1 (1) ◽  
pp. 3-35 ◽  
Author(s):  
Judy Sterner ◽  
Nicholas David

The publication, largely by ethnoarchaeologists, of new data on the tamper and concave anvil technique of pot-forming (TCA) permits a reassessment of this uniquely African technique, its toolkit, and its culture history. A survey, inspired by the technologie culturelle school, of its varied expressions in the southern Saharan, Sahelian and northern Sudan zones from Mali to Sudan and extending north into Egypt emphasises the potential of the technique for the efficient production of spherical water jars of high volume to weight ratio, much appreciated in arid environments. The technique is demanding and therefore practised for the most part by specialists. The origins and diffusion of the technique are assessed in the light of the ethnological, archaeological, linguistic, and historical evidence, and a four stage historical development is sketched.


Author(s):  
Jeffrey P. Copeland ◽  
Arild Landa ◽  
Kimberly Heinemeyer ◽  
Keith B. Aubry ◽  
Jiska van Dijk ◽  
...  

Social behaviour in solitary carnivores has long been an active area of investigation but for many species remains largely founded in conjecture compared to our understanding of sociality in group-living species. The social organization of the wolverine has, until now, received little attention beyond its portrayal as a typical mustelid social system. In this chapter the authors compile observations of social interactions from multiple wolverine field studies, which are integrated into an ecological framework. An ethological model for the wolverine is proposed that reveals an intricate social organization, which is driven by variable resource availability within extremely large territories and supports social behaviour that underpins offspring development.


Author(s):  
Samir Okasha

Inclusive fitness theory, originally due to W. D. Hamilton, is a popular approach to the study of social evolution, but shrouded in controversy. The theory contains two distinct aspects: Hamilton’s rule (rB > C); and the idea that individuals will behave as if trying to maximize their inclusive fitness in social encounters. These two aspects of the theory are logically separable but often run together. A generalized version of Hamilton’s rule can be formulated that is always true, though whether it is causally meaningful is debatable. However, the individual maximization claim only holds true if the payoffs from the social encounter are additive. The notion that inclusive fitness is the ‘goal’ of individuals’ social behaviour is less robust than some of its advocates acknowledge.


Author(s):  
Samuel K. Cohn, Jr.

This chapter examines evidence principally from the US that the Great Influenza provoked profiteering by landlords, undertakers, vendors of fruit, pharmacists, and doctors, but shows that such complaints were rare and confined mostly to large cities on the East Coast. It then investigates anti-social advice and repressive decrees on the part of municipalities, backed by advice from the US Surgeon General and prominent physicians attacking ‘spitters, coughers, and sneezers’, which included state and municipal ordinances against kissing and even ‘big talkers’. It then surveys legislation on compulsory and recommended mask wearing. Yet this chapter finds no protest or collective violence against the diseased victims or any other ‘others’ suspected of disseminating the virus. Despite physicians’ and lawmakers’ encouragement of anti-social behaviour, mass volunteerism and abnegation instead unfolded to an extent never before witnessed in the world history of disease.


Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2135
Author(s):  
Kamila Butowska ◽  
Anna Woziwodzka ◽  
Agnieszka Borowik ◽  
Jacek Piosik

Doxorubicin, a member of the anthracycline family, is a common anticancer agent often used as a first line treatment for the wide spectrum of cancers. Doxorubicin-based chemotherapy, although effective, is associated with serious side effects, such as irreversible cardiotoxicity or nephrotoxicity. Those often life-threatening adverse risks, responsible for the elongation of the patients’ recuperation period and increasing medical expenses, have prompted the need for creating novel and safer drug delivery systems. Among many proposed concepts, polymeric nanocarriers are shown to be a promising approach, allowing for controlled and selective drug delivery, simultaneously enhancing its activity towards cancerous cells and reducing toxic effects on healthy tissues. This article is a chronological examination of the history of the work progress on polymeric nanostructures, designed as efficient doxorubicin nanocarriers, with the emphasis on the main achievements of 2010–2020. Numerous publications have been reviewed to provide an essential summation of the nanopolymer types and their essential properties, mechanisms towards efficient drug delivery, as well as active targeting stimuli-responsive strategies that are currently utilized in the doxorubicin transportation field.


Zootaxa ◽  
2017 ◽  
Vol 4272 (4) ◽  
pp. 551
Author(s):  
ROY A. NORTON ◽  
SERGEY G. ERMILOV

Based on the study of type material, other historical specimens, and new collections, the adult of the thelytokous oribatid mite Oribata curva Ewing, 1907 (Galumnidae) is redescribed and the name is recombined to Trichogalumna curva (Ewing, 1907) comb. nov. A confusing history of synonymies and misidentifications is traced in detail, and their effect on published statements about biogeography is assessed. Reliable records of T. curva are only those from North America. The tropical mite Pergalumna ventralis (Willmann, 1932) is not a subspecies of T. curva. The widely-reported Trichogalumna nipponica (Aoki, 1966) and other similar species form a complex with T. curva that needs further morphological and molecular assessment. 


1873 ◽  
Vol 10 (111) ◽  
pp. 385-395 ◽  
Author(s):  
T. Sterry Hunt

It is proposed in the following pages to give a concise account of the progress of investigation of the lower Palæozoic rocks during the last forty years. The subject may naturally be divided into three parts: 1. The history of Silurian and Upper Cambrian in Great Britain from 1831 to 1854; 2. That of the still more ancient Palæozoic rocks in Scandinavia, Bohemia, and Great Britain up to the present time, including the recognition by Barrande of the so-called primordial Palæozoic; fauna; 3. The history of the lower Palæozoic rocks of North America.


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