https://www.posetteforever.com/viewtopic.php?f=64&t=3930&p=45004#p45004 ----------------------------------- Nik Monday, 26 June 2017, 02:37 PM How To Let An Exoskeletal Mega-bug Grow Without Moulting... ----------------------------------- I've been scratching my head over the biology of those 'Big Bad Bugs'... Biggest problem after limb articulation is how they can grow. Terran bugs moult. None, even during the oxygen-rich Carboniferous etc, got big enough ON LAND to be really, really scary. Biggest now are tree-climbing 'Robber Crabs'. Though they've evolved 'book lungs', they must go back to the sea to spawn... Then I remembered the humble tortoise. Arguably, it has an exoskeleton of sorts. But, it grows without moulting... Some digging through my half-forgotten 'Recreational Maths' brought me to 'Reuleaux' figures. A pentagonal version would provide an anatomical shape, growth planes etc etc. And, if limbs are shaped thus in cross-section, they would allow joints at various combinations of 72ยบ. Now, how to articulate limbs so BBBs can groom themselves or scrape off hitch-hikers ??