جريدة الجمهور نبض الشعب وقلب الحقيقة
Right here, we control the brand new numerous independent evolutionary roots regarding four-club linkage options (Contour step one) to test just how morphological and you may mechanical correlations feeling one or two secret facets regarding morphological advancement: speed (rate from which morphological disparity can add up) and you will setting (evolutionary trend regarding feature changes round the phylogeny). Four-pub linkages is closed-chain assistance comprised of four strict links that become to send motion and you can push (Anker, 1974; Muller, 1996; Westneat, 1990; Martins, 1994) (Figure 1A). Technical productivity out of four-pub linkages is oftentimes mentioned with respect to kinematic alert (KT), a straightforward metric that will measure a great tradeoff between displacement and you will push across other linkage configurations (pick Content and methods point for further details about KT). Four-club linkages was widespread in nature, and enable a wealthy range off behavior inside vertebrates and you may invertebrates (Westneat, 1990; Wainwright et al., 2005; Patek et al., 2007; Olsen and you may Westneat, 2016). For example, four-bar linkages actuate lips starting for sucking eating when you look at the fishes (Westneat, 1990; Martins, 1994; Muller, 1987), bending and you will expansion of the vertebrate knee (Hobson and you may Torfason, 1974), quick effects of your stomatopod raptorial appendage (Patek et al., 2004; Patek ainsi que al., 2007; McHenry mais aussi al., 2012; McHenry mais aussi al., 2016), and head kinesis from inside the birds (Hoese and you can Westneat, 1996).
Four-pub linkage expertise have evolved alone several times round the animals and you will are composed of four rotatable backlinks you to shown motion and you will push.
(A) Four-club linkages consist of a predetermined hook (black) and you will three mobile hyperlinks: enter in (orange), yields (red), and you can coupler (blue). (B) Regarding raptorial appendages of mantis shrimp (Stomatopoda), rotation of the input connect (meral-V, m-V, which is area of the merus part, me) causes the latest efficiency hook (carpus, ca) so you’re able to become external, which then rapidly rotates the latest dactyl (da). (C) Throughout the dental four-club system one to advanced by themselves when you look at the labrid and you will cichlid fishes, the latest input link (down chin, lj) rotates ventrally, causing rotation throughout the nose (na) plus in the output connect (maxilla, mx), leading to premaxillary (pmx) protrusion. (D) On the opercular four-bar linkage system of centrarchid fish, new type in hook up (opercle and you may subopercle, op) shifts posteriorly, because does the fresh interopercle (iop). That it activity is transmitted on the productivity connect (retroarticular processes on mandible, ra), that triggers the new mandible so you can change ventrally and you will unlock the low mouth. (B–D) Dashed lines signify the latest finalized setting out-of enter in (orange), efficiency (red), and coupler (blue) links, while strong lines denote the discover configuration pursuing the activity. Arrows signify the direction of motion.
Four-bar linkages as well as showcase mechanized sensitivity, and this happens when KT is actually disproportionately sensitive to version in some website links and apparently insensitive in order to adaptation in others (Anderson and you may Patek, 2015; Munoz ainsi que al
Four-club linkages, like most system created of three or even more bits, display of a lot-to-one mapping, and thus equivalent mechanized outputs (elizabeth.g. KT) can be produced as a consequence of other combinations out-of morphology (e.grams. hook up lengths; Wainwright ainsi que al., 2005; Wainwright, 2007). , 2017). Hence, four-club linkages exhibit (1) each other poor and you will strong correlations one of bits and randki matchocean outputs and you will (2) numerous evolutionary roots over the Metazoa. Therefore, four-pub linkages is a fertile investigations surface to possess comparative analyses out of evolutionary biomechanics and you will morphology.
To our studies, the partnership anywhere between physical susceptibility and you can morphological advancement has only been analyzed from the five-pub linkage program of one’s mantis shrimp (Stomatopoda) raptorial appendage (Munoz ainsi que al., 2017; Anderson and you may Patek, 2015) (Contour step 1). The newest mantis shrimp four-club experience employed for giving, assaulting, and you can substrate manipulation thru extremely rapid influences of the raptorial appendages (Patek et al., 2004;Patek mais aussi al., 2007; Patek mais aussi al., 2013; Patek and you may Caldwell, 2005; McHenry mais aussi al., 2016; deVries et al., 2012; Environmentally friendly and you will Patek, 2015; Green and you can Patek, 2018; Crane mais aussi al., 2018). Spearing stomatopods one to harpoon mobile, soft-bodied victim provides higher KT (greater displacement) than smashing mantis shrimp that bludgeon hard-shelled target having fun with linkages which have down KT (deeper force) (Anderson et al., 2014; McHenry ainsi que al., 2016). From inside the mantis shrimp, physical awareness was from the expidited progression: the web link most securely synchronised which have KT showcases the quickest rates away from progression (Munoz et al., 2017).