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Our knowledge about the sexual transmission of mitochondria and plastids (hereafter organelles) in isogamous eukaryotes comes mostly from studies of the yeast Saccharomyces cerevisiae and the green alga Chlamydomonas reinhardtii which are both unicellular species. To investigate organelle inheritance in a multicellular organism with ...


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Suppose a gene performs two distinct functions 1 and 2, both of which are essential. We'll call this gene A, for ancestral gene. A duplication copies A to another locus. Now there are two genes, A and B, that perform the same two functions. At this point, if either A or B is deleted, the organism is fine. Over evolutionary time, A and B undergo genetic ...


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There are many different ways to do this, depending on what assumptions you make on e.g. stable age structure, distribution of offspring, haploidy/diploidy, population growth etc. As you probably know, there are also two main approaches to effective population sizes, namely ones based on; 1) the rate of inbreeding ($N_{e,i}$) and 2) the increase in variance ...


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From Conner and Hartl's A primer of ecological genetics: "Any variance in reproductive success among individuals greater than random expectations, a commonplace concurrence in natural populations, reduces effective population size." So yes, selection does reduce the effective population size and for the reason you suggest - it removes some ...


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You can't predict the evolution of anything because evolution is driven solely by the environment. It is the environment that squeezes species into to specific forms. We have has a much say in our shape and form as a whirlpool does and for the same reasons, both humans and whirlpools result form powerful outside forces. In order to have shot at even making ...


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Grey hair is one of many age related traits. Other traits showing a positive correlation with age include Parkinson's, cancer, and Alzheimer's. There are two key theories as to why age-related disease & decline occurs. But the key message is just because something evolves, it doesn't mean it's advantageous. First of all is mutation accumulation (MA) ...


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I have not posted or read much on this forum before but thought I would throw in my two cents. Perhaps a more accurate and comprehensive term is "reproductive selection". This would include "sexual selection (eg qualities making an individual more attractive to the opposite sex) and "survival selection" - to the extent that survival allows one to produce ...


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"I imagine that turtle looking up at that food, and sub-consciously wishing to get to it, constantly straining, for it's entire life time. It seems plausible to me that we (advanced life) could have a biological mechanism to "write" needed alterations into either our own DNA or our reproductive DNA over time, triggering the very specific ...


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This article claims to be a new level of evidence for group selection. Its a little early to tell at this point whether the critics will be moved. They have not been in the past! sorry if this is a bit short - its late, but i'll try to come back and do more later..


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As canalization is defined in your question (also in wikipedia) it means robustness. Semantically it is possible to differentiate the two. Robustness of a system refers to its sensitivity to perturbations. In other words small differences in parameters would not affect the steady state of the system (parameter changes in a physically plausible range ...


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Hansen (2006) says (middle of page 19): A link between genetic and environmental robustness is plausible, because genetic en environmental disturbances ay often affect the same functional pathways in the organism, and any increase int he robustness has been fund in studies of RNA folding (Ancel & Fontana 2000), in the effects of heat-shock proteins ...



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