A Hypothesis Suggesting a Single Origin of Agriculture

1977 ◽  
pp. 89-134 ◽  
2012 ◽  
Vol 39 (2) ◽  
pp. 217-233 ◽  
Author(s):  
J. David Archibald

Studies of the origin and diversification of major groups of plants and animals are contentious topics in current evolutionary biology. This includes the study of the timing and relationships of the two major clades of extant mammals – marsupials and placentals. Molecular studies concerned with marsupial and placental origin and diversification can be at odds with the fossil record. Such studies are, however, not a recent phenomenon. Over 150 years ago Charles Darwin weighed two alternative views on the origin of marsupials and placentals. Less than a year after the publication of On the origin of species, Darwin outlined these in a letter to Charles Lyell dated 23 September 1860. The letter concluded with two competing phylogenetic diagrams. One showed marsupials as ancestral to both living marsupials and placentals, whereas the other showed a non-marsupial, non-placental as being ancestral to both living marsupials and placentals. These two diagrams are published here for the first time. These are the only such competing phylogenetic diagrams that Darwin is known to have produced. In addition to examining the question of mammalian origins in this letter and in other manuscript notes discussed here, Darwin confronted the broader issue as to whether major groups of animals had a single origin (monophyly) or were the result of “continuous creation” as advocated for some groups by Richard Owen. Charles Lyell had held similar views to those of Owen, but it is clear from correspondence with Darwin that he was beginning to accept the idea of monophyly of major groups.


2019 ◽  
Vol 11 (5) ◽  
pp. 1319 ◽  
Author(s):  
Mangku Purnomo ◽  
Pardamean Daulay ◽  
Medea Utomo ◽  
Sugeng Riyanto

Between agro-food products, coffee is the first commodity to quarrel in ethical attributes and sustainability issues such as fair trade, premium prices, as well as justified value chain issues. Taking into account the growing coffee consumption in Indonesia, this article tries to prove connoisseur consumers (CCs) are moderating the sustainable consumption and dynamics capabilities (DCs) of single origin coffee shops (SOCSs). An in-depth interview to 30 SOCS managers and 60 baristas and a survey to 450 consumers found that there are significant correlations between connoisseurs attributes such as the depth of a barista’s knowledge of coffee, the barista’s skills, the shop image, the coffee variation, the barista’s communication skills, and the serving techniques and that they have a relationship with an increase in the number of consumers. The existence of CCs has encouraged the practice of consumption sustainability of SOCSs and moderates SOCSs to improve sensing, seizing, and transforming shop management to stand against the competition. Based on the above findings, more in-depth research on the standard character and number of CCs is needed as well as their contribution to the revenue structure of SOCSs. Meanwhile, connoisseur customers’ support is capable of helping the SOCSs in improving their DCs to improve the sustainable consumption of Indonesian single origin coffee in the future.


2011 ◽  
Vol 61 (2) ◽  
pp. 245-254 ◽  
Author(s):  
Daniel L. Distel ◽  
Mehwish Amin ◽  
Adam Burgoyne ◽  
Eric Linton ◽  
Gustaf Mamangkey ◽  
...  

Mycologia ◽  
2011 ◽  
Vol 103 (1) ◽  
pp. 45-56 ◽  
Author(s):  
Geir Hestmark ◽  
Jolanta Miadlikowska ◽  
Frank Kauff ◽  
Emily Fraker ◽  
Katalin Molnar ◽  
...  
Keyword(s):  

1997 ◽  
Vol 77 (2) ◽  
pp. 554-561 ◽  
Author(s):  
Jong-Nam Kim ◽  
Kathleen Mulligan ◽  
Helen Sherk

Kim, Jong-Nam, Kathleen Mulligan, and Helen Sherk. Simulated optic flow and extrastriate cortex. I. Optic flow versus texture. J. Neurophysiol. 77: 554–561, 1997. A locomoting observer sees a very different visual scene than an observer at rest: images throughout the visual field accelerate and expand, and they follow approximately radial outward paths from a single origin. This so-called optic flow field is presumably used for visual guidance, and it has been suggested that particular areas of visual cortex are specialized for the analysis of optic flow. In the cat, the lateral suprasylvian visual area (LS) is a likely candidate. To test the hypothesis that LS is specialized for analysis of optic flow fields, we recorded cell responses to optic flow displays. Stimulus movies simulated the experience of a cat trotting slowly across an endless plain covered with small balls. In different simulations we varied the size of balls, their organization (randomly or regularly dispersed), and their color (all one gray level, or multiple shades of gray). For each optic flow movie, a “texture” movie composed of the same elements but lacking optic flow cues was tested. In anesthetized cats, >500 neurons in LS were studied with a variety of movies. Most (70%) of 454 visually responsive cells responded to optic flow movies. Visually responsive cells generally preferred optic flow to texture movies (69% of those responsive to any movie). The direction in which a movie was shown (forward or reverse) was also an important factor. Most cells (68%) strongly preferred forward motion, which corresponded to visual experience during locomotion.


1999 ◽  
Vol 86 (4) ◽  
pp. 554-562 ◽  
Author(s):  
Nikolai Friesen ◽  
Sven Pollner ◽  
Konrad Bachmann ◽  
Frank R. Blattner

1988 ◽  
Vol 90 (4) ◽  
pp. 958-965 ◽  
Author(s):  
Michael J. O'Brien ◽  
H. Clyde Wilson

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