Chi-Hing Christina Cheng

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The Notothenioidei dominates the fish fauna of the Antarctic in both biomass and diversity. This clade exhibits adaptations related to metabolic function and freezing avoidance in the subzero Antarctic waters, and is characterized by a high degree of morphological and ecological diversity. Investigating the macroevolutionary processes that may have(More)
The fish fauna of the Antarctic Ocean is dominated by five endemic families of the Perciform suborder Notothenioidei, thought to have arisen in situ within the Antarctic through adaptive radiation of an ancestral stock that evolved antifreeze glycoproteins (AFGPs) enabling survival as the ocean chilled to subzero temperatures. The endemism results from(More)
The antifreeze glycoprotein-fortified Antarctic notothenioid fishes comprise the predominant fish suborder in the isolated frigid Southern Ocean. Their ecological success undoubtedly entailed evolutionary acquisition of a full suite of cold-stable functions besides antifreeze protection. Prior studies of adaptive changes in these teleost fishes generally(More)
Antarctic notothenioids, along with many other polar marine fishes, have evolved biological antifreeze proteins (AFPs) to survive in their icy environments. The larvae of Antarctic notothenioid fish hatch into the same frigid environment inhabited by the adults, suggesting that they must also be protected by sufficient AFPs, but this has never been(More)
The noncolligative peptide and glycopeptide antifreezes found in some cold-water fish act by binding to the ice surface and preventing crystal growth, not by altering the equilibrium freezing point of the water. A simple crystal growth and etching technique allows determination of the crystallographic planes where the binding occurs. In the case of(More)
The evolutionary model escape from adaptive conflict (EAC) posits that adaptive conflict between the old and an emerging new function within a single gene could drive the fixation of gene duplication, where each duplicate can freely optimize one of the functions. Although EAC has been suggested as a common process in functional evolution, definitive cases(More)
The eye lenses of the Antarctic nototheniid fishes that inhabit the perennially freezing Antarctic seawater are transparent at -2 degrees C, whereas the cold-sensitive mammalian and tropical fish lenses display cold-induced cataract at 20 degrees C and 7 degrees C, respectively. No cold-cataract occurs in the giant Antarctic toothfish Dissostichus mawsoni(More)
Phylogenetically diverse polar and subpolar marine teleost fishes have evolved antifreeze proteins (AFPs) or antifreeze glycoproteins (AFGPs) to avoid inoculative freezing by internalized ice. For over three decades since the first fish antifreeze (AF) protein was discovered, many studies of teleost freezing avoidance showed hepatic AF synthesis and(More)
Notothenioids represent an adaptive radiation of teleost fishes in the frigid and ice-laden waters of the Southern Ocean surrounding Antarctica. Phylogenetic hypotheses for this clade have resulted primarily from analyses of mtDNA gene sequences, and studies utilizing nuclear gene DNA sequence data have focused on particular sub-clades of notothenioid(More)