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TRANSPOSON CONTROL. "Plants, as well as other highly developed multicellular organisms, show increased DNA methylation when compared with other eukaryotic organisms, probably due to the need for more efficient control of transposons, or the need for additional epigenetic regulation to control the development of many different cell types." http://jxb.oxfordjournals.org/content/62/11/3713.full View in LinkedIn

"PLANT CELL DEDIFFERENTIATION has been mostly studied in protoplast systems. In such experimental systems dedifferentiation can be resolved into acquisition of competence for pluripotentiality and signal-dependent re-entry into S phase, each phase being accompanied by a broad chromatin decondensation. For reactivation of the cell cycle it is usually necessary that plant growth regulators are applied, but this occurs independently from the acquisition of competence for pluripotentiality." http://jxb.oxfordjournals.org/content/62/11/3713.full View in LinkedIn

PLANT DEDIFFERENTIATION. "In response to specific environmental signals, cells acquire competence to switch fate which is accomplished by going through a dedifferentiation process followed by the implementation of a new developmental pathway. This sequence of events is accompanied by changes at the chromatin level and reprogramming of gene expression, highlighting the central role of epigenetic regulation in these processes." http://jxb.oxfordjournals.org/content/62/11/3713.full View in LinkedIn

BIOLOGY NOT PHILOSOPHY. “I hasten to add that I am an experimental biologist, not a philosopher, so I cannot claim to offer anything to this fascinating philosophical tradition. What I propose to offer, rather, is a description of what I believe to be an interesting example of how biosemiotic principles can constructively inform questions of how adaptation, and hence evolution, works. This is the “extended organism” embodied in colonies of the mound-building termites that are widespread throughout southern Africa (Macrotermes spp., Macrotermitinae).” https://link.springer.com/article/10.1007/s12304-016-9256-5 View in LinkedIn

THE CASE STUDY. “I review our findings on one such example: the mounds built by the fungus-cultivating termites of the genus Macrotermes. These structures are dynamic forms that are sustained by flows of soil from deep horizons up into the mound. The form, and hence the function, of the mound is determined by several environmental cues, most notably water and wind, as well as how termites interpret these cues, and signals that flow between termites, both directly and vicariously through the structures they build.” https://link.springer.com/article/10.1007/s12304-016-9256-5 View in LinkedIn

RESOLVING INCOHERENCES. “This is well-illustrated by the constructed environments built by colonies of social insects, such as hives or nests, and the ancillary structures that contain them, forming an organism-like system known as a superorganism. The superorganism is marked by a kind of extended physiology, in that these constructed environments often serve as adaptive interfaces between the nest and ambient environment, and are constructed to manage the matter and energy flows between environments that constitute the process of adaptation. These constructed environments are also semiotic phenomena: interpretive structures, governed by information flow between the member insects and the structures they build.” https://link.springer.com/article/10.1007/s12304-016-9256-5 View in LinkedIn

“MODERN DARWINISM has come to focus almost exclusively on hereditary memory, eclipsing the—arguably still-problematic—phenomenon of adaptation. As a result, modern Darwinism retains, at its core, certain incoherencies that, as long as they remain unresolved, preclude the emergence of a fully-coherent theory of evolution. Resolving the incoherencies will involve clarifying the relationship between embodied memory and apt function. In short, adaptation is a problem of semiotics: the organism must interpret the environment to fit well into it.” https://link.springer.com/article/10.1007/s12304-016-9256-5 View in LinkedIn