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Model hard colloids have a great deal of relevance to physics and in particular the study of their phase behavior which can mimic that of simple atomic liquids and solids. "Nearly hard colloidal sphere" suspensions were formulated 35 years ago by the Ottewill group (Univ. of Bristol) and Imperial Chemical Industries Ltd., which were used by Pusey and van Megen in their seminal study of the phase behavior of hard-sphere colloids. We report on our efforts to reproduce and refine this benchmark polymer colloid, including the recent synthesis of hard ellipsoids for random and ordered packing studies in microgravity*. The custom-made samples are composed of linear polymer chains of poly(methyl methacrylate), functionalized with photo-crosslinkable moieties and fluorescent molecules. The resulting ellipsoidal shapes are about 1 micron in size and stabilized with surface-grafted poly(12-hydroxystearic acid) chains. The particles are dispersed in a refractive index matching fluid and particle aspect ratios vary from 1 to 4. * Launched March 2020 aboard SpaceX CRS-20 resupply service mission to the International Space Station. *NASA NNX13AR67G (NYU); NSF GOALI 1832291 (NYU); NSF GOALI 1832260 (NJIT) 

Echinoderms are an exceptional group of bilaterians that develop pentameral adult symmetry from a bilaterally symmetric larva. However, the genetic basis in evolution and development of this unique transformation remains to be clarified. Here we report newly sequenced genomes, developmental transcriptomes, and proteomes of diverse echinoderms including the green sea urchin (L. variegatus), a sea cucumber (A. japonicus), and with particular emphasis on a sister group of the earliest-diverged echinoderms, the feather star (A. japonica). We learned that the last common ancestor of echinoderms retained a well-organized Hox cluster reminiscent of the hemichordate, and had gene sets involved in endoskeleton development. Further, unlike in other animal groups, the most conserved developmental stages were not at the body plan establishing phase, and genes normally involved in bilaterality appear to function in pentameric axis development. These results enhance our understanding of the divergence of protostomes and deuterostomes almost 500 Mya.