Is Sequence Heterochrony an Important Evolutionary Mechanism in Mammals?

2003 ◽  
Vol 10 (4) ◽  
pp. 335-361 ◽  
Author(s):  
Olaf R. P. Bininda-Emonds ◽  
Jonathan E. Jeffrey ◽  
Michael K. Richardson
2003 ◽  
Vol 30 (1) ◽  
pp. 85-96 ◽  
Author(s):  
Kim Kleinman

On at least four occasions, Edgar Anderson (1897–1969) began revising his book Plants, man and life (1952). Given both its place in Anderson's career and his place in the development of evolutionary theory in the mid-twentieth century, the emendations are noteworthy. Though a popular work, Plants, man and life served as the distillation of Anderson's ideas on hybridization as an evolutionary mechanism, the need for more scientific attention on domesticated and semi-domesticated plants, and the opportunities such plants provided for the study of evolution. Anderson was an active participant in several key events in what historians have come to call the Evolutionary Synthesis. For example, he and Ernst Mayr shared the 1941 Jesup Lectures on “Systematics and the origin of species”. Anderson's proposed revisions to his book reflect both an attempt to soften certain acerbic comments as well as an attempt to recast the book as a whole.


Author(s):  
Robert N. Spengler

AbstractOver the past decade, niche construction theory (NCT) has been one of the fastest-growing theories or scholarly approaches in the social sciences, especially within archaeology. It was proposed in the biological sciences 25 years ago and is often referred to as a neglected evolutionary mechanism. Given its rapid acceptance by the archaeological community, it is important that scholars consider how it is being applied and look for discrepancies between applications of the concept. Many critical discussions of NCT have already been published, but most of them are in biology journals and may be overlooked by scholars in the social sciences. In this manuscript, my goal is to synthesis the criticisms of NCT, better allowing archaeologists to independently evaluate its usefulness. I focus on the claims of novelty and differences between NCT and other approaches to conceptualizing anthropogenic ecosystem impacts and culture-evolution feedbacks. I argue that the diverse concepts currently included in the wide-reaching purview of NCT are not new, but the terminology is and may be useful to some scholars. If proponents of the concept are able to unify their ideas, it may serve a descriptive function, but given that lack of a testable explanatory mechanism, it does not have a clear heuristic function.


2010 ◽  
Vol 23 (2) ◽  
pp. 94 ◽  
Author(s):  
Judita Lihová ◽  
Hiroshi Kudoh ◽  
Karol Marhold

Polyploidy is an important evolutionary mechanism and speciation mode in plants; however, delimitation of species boundaries in polyploid complexes is often a difficult task. In the present paper, we explore morphological variation in a group of East Asian Cardamine polyploids that have long been shrouded in taxonomic and nomenclatural confusion. We relate the present morphometric data of 41 sampled populations with recently published ploidy-level data, and propose a revised taxonomic treatment, including the designation of several lectotypes. The following species are recognised in Japan: C. schinziana O.E.Schulz (2n = 6x, 8x), C. torrentis Nakai (2n = 8x), C. valida (Takeda) Nakai (2n = 4x) and C. yezoensis Maxim. (2n = 6x−12x). C. amariformis Nakai (2n = 4x) from Korea is also discussed, although it may be conspecific with C. valida, pending further studies. Distribution of these taxa in the Japanese Archipelago is characterised, including comments on their occurrence outside of Japan.


2012 ◽  
Vol 36 (3) ◽  
pp. 521-527 ◽  
Author(s):  
MARTIN SCHLIEP ◽  
GERMÁN CAVIGLIASSO ◽  
ROSANNE G. QUINNELL ◽  
ROBERT STRANGER ◽  
ANTHONY W. D. LARKUM

2019 ◽  
Vol 84 ◽  
pp. 1100-1107 ◽  
Author(s):  
Zhi-long Chen ◽  
Bei-Ni Gong ◽  
Qi-long Wang ◽  
Zhi-hui Xiao ◽  
Chong Deng ◽  
...  

2020 ◽  
Author(s):  
James H Kaufman ◽  
Ignacio Terrizzano ◽  
Gowri Nayar ◽  
Ed Seabolt ◽  
Akshay Agarwal ◽  
...  

AbstractHorizontal gene transfer mediated by integrative and conjugative elements (ICE) is considered an important evolutionary mechanism of bacteria. It allows organisms to quickly evolve new phenotypic properties including antimicrobial resistance (AMR) and virulence. The rate of ICE-mediated cargo gene exchange has not yet been comprehensively studied within and between bacterial taxa. In this paper we report a big data analysis of ICE and associated cargo genes across over 200,000 bacterial genomes representing 1,345 genera. Our results reveal that half of bacterial genomes contain one or more known ICE features (“ICE genomes”), and that the associated genetic cargo may play an important role in the spread of AMR genes within and between bacterial genera. We identify 43 AMR genes that appear only in ICE genomes and never in non-ICE genomes. A further set of 95 AMR genes are found >5x more often in ICE versus non-ICE genomes. In contrast, only 29 AMR genes are observed more frequently (at least 5:1) in non-ICE genomes compared to ICE genomes. Analysis of NCBI antibiotic susceptibility assay data reveals that ICE genomes are also over-represented amongst phenotypically resistant isolates, suggesting that ICE processes are critical for both genotypic and phenotypic AMR. These results, as well as the underlying big data resource, are important foundational tools for understanding bacterial evolution, particularly in relation to important bacterial phenotypes such as AMR.


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