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SIMPLE ORGANISM, COMPLEX BEAST. "Consider this sobering lesson: the roundworm Caenorhabditis elegans is a tiny creature whose brain has 302 nerve cells. Back in 1986, scientists used electron microscopy to painstakingly map its roughly 6000 chemical synapses and its complete wiring diagram. Yet more than two decades later, there is still no working model of how this minimal nervous system functions." https://lnkd.in/dUt32Gf View in LinkedIn

OPEN WORM PROJECT. "The open source project recently had its first major breakthrough when its software -- modeled on the neurons of the worm's nervous system -- independently controlled a Lego robot. The machine's sensors, without any prior programming, made the robot behave in a similar fashion to C. elegans, approaching and backing away from obstacles or stimulated by food." https://lnkd.in/dfAzF4Z View in LinkedIn

C. ELEGANS, the OpenWorm subject. “The connectome of this complex/simp,e creature has been mapped. That has been simulated and transmitted to code, which has been used to drive a robot.” https://lnkd.in/d3p9Grs View in LinkedIn

THE LOGIC. “There exists also a limited domain in parameter space (in which costs to mate finding are moderate), in which collapse from four mating-types to three is possible, but the collapse from three to two is not. If costs to not finding a mate are high then it is expected that gametic fusion should be abandoned for a system in which nuclei are exchanged but cytoplasm is not.” http://rspb.royalsocietypublishing.org/content/263/1369/415.short View in LinkedIn

CYTOPLASMIC GENES. “Species with two mating-types coordinate uniparental inheritance of cytoplasmic genes more efficiently than do those with three, then, assuming the costs to mate finding are not too high, evolution from three to two sexes is expected as a response to the invasion of a costly selfish cytoplasmic factor that disrupts the normal pattern of inheritance.” http://rspb.royalsocietypublishing.org/content/263/1369/415.short View in LinkedIn

BIOECONOMICS. “By the same logic, two mating-types is the least expected state. A demonstration of the evolution from three to two sexes, under the condition of costs to mate-finding, has yet to be provided.” http://rspb.royalsocietypublishing.org/content/263/1369/415.short View in LinkedIn

INFINITE SEXES. “Populations of most isogamous protists have gametes that belong to one of only two mating-types (alias sexes). That this should be so is paradoxical for, if there is any cost involved in the finding of a mate, then a gamete of a third mating-type would, at the point of invasion, be able to mate with the first gamete it encounters, hence suffering the minimum possible costs. The expectation is hence that the number of mating-types in most isogamous species should tend towards infinity.” https://lnkd.in/d9iAAMt View in LinkedIn

ONE NORM. “In animals and plants that have evolved separate sexes, accurate differentiation into fertile males and females is a fundamental developmental process.” https://lnkd.in/dHNc_hg View in LinkedIn