Resource Allocation and the Evolution of Self-Fertilization in Plants

2000 ◽  
Vol 155 (2) ◽  
pp. 187
Author(s):  
Zhang
2018 ◽  
Author(s):  
Roshni G. Iyer ◽  
D. Valle Rogers ◽  
Christopher J. Winchell ◽  
David A. Weisblat

ABSTRACTLeeches and oligochaetes comprise a monophyletic group of annelids, the Clitellata, whose reproduction is characterized by simultaneous hermaphroditism. While most clitellate species reproduce by cross-fertilization, self-fertilization has been described within the speciose genus Helobdella. Here we document the reproductive life histories and reproductive capacities for three other Helobdella species. Under laboratory conditions, both H. robusta and H. octatestisaca exhibit uniparental reproduction, apparently reflecting self-fertility, and suggesting that this trait is ancestral for the genus. However, the third species, H. austinensis, seems incapable of reproduction by self-fertilization, so we inferred its reproductive life history by analyzing reproduction in breeding cohorts. Comparing the reproductive parameters for H. robusta reproducing in isolation and in cohorts revealed that reproduction in cohorts is dramatically delayed with respect to that of isolated individuals, and that cohorts of leeches coordinate their cocoon deposition in a manner that is not predicted from the reproductive parameters of individuals reproducing in isolation. Finally, our comparisons of reproductive capacity for individuals versus cohorts for H. robusta, and between different sizes of cohorts for H. austinensis, reveal differences in resource allocation between male and female reproductive roles that are consistent with evolutionary theory.


2018 ◽  
Vol 41 ◽  
Author(s):  
Neil Malhotra

AbstractAlthough Boyer & Petersen's (B&P's) cataloguing of and evolutionary explanations for folk-economic beliefs is important and valuable, the authors fail to connect their theories to existing explanations for why people do not think like economists. For instance, people often have moral intuitions akin to principles of fairness and justice that conflict with utilitarian approaches to resource allocation.


2012 ◽  
Vol 43 (4) ◽  
pp. 232-242 ◽  
Author(s):  
Phia S. Salter ◽  
Glenn Adams

Inspired by “Mother or Wife” African dilemma tales, the present research utilizes a cultural psychology perspective to explore the dynamic, mutual constitution of personal relationship tendencies and cultural-ecological affordances for neoliberal subjectivity and abstracted independence. We administered a resource allocation task in Ghana and the United States to assess the prioritization of conjugal/nuclear relationships over consanguine/kin relationships along three dimensions of sociocultural variation: nation (American and Ghanaian), residence (urban and rural), and church membership (Pentecostal Charismatic and Traditional Western Mission). Results show that tendencies to prioritize nuclear over kin relationships – especially spouses over parents – were greater among participants in the first compared to the second of each pair. Discussion considers issues for a cultural psychology of cultural dynamics.


2018 ◽  
Vol 30 (4) ◽  
pp. 196-206 ◽  
Author(s):  
Byungho Park ◽  
Rachel L. Bailey

Abstract. In an effort to quantify message complexity in such a way that predictions regarding the moment-to-moment cognitive and emotional processing of viewers would be made, Lang and her colleagues devised the coding system information introduced (or ii). This coding system quantifies the number of structural features that are known to consume cognitive resources and considers it in combination with the number of camera changes (cc) in the video, which supply additional cognitive resources owing to their elicitation of an orienting response. This study further validates ii using psychophysiological responses that index cognitive resource allocation and recognition memory. We also pose two novel hypotheses regarding the confluence of controlled and automatic processing and the effect of cognitive overload on enjoyment of messages. Thirty television advertisements were selected from a pool of 172 (all 20 s in length) based on their ii/cc ratio and ratings for their arousing content. Heart rate change over time showed significant deceleration (indicative of increased cognitive resource allocation) for messages with greater ii/cc ratios. Further, recognition memory worsened as ii/cc increased. It was also found that message complexity increases both automatic and controlled allocations to processing, and that the most complex messages may have created a state of cognitive overload, which was received as enjoyable by the participants in this television context.


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