Genome sizes vary by orders of magnitude across the Tree of Life and lack any correlation with organismal complexity. Some crustacean orders, such as amphipods, have genome sizes that correlate with body size, temperature, and water depth, indicating that natural selection may constrain genome sizes due to physiological pressures. In this study, we examine the relationship between genome size, repetitive content, and environmental variables on a clade of sand-burrowing amphipods (Haustoriidae) that are distributed across the Gulf of Mexico and the North Atlantic. We uncover a 6-fold genome size variation within a clade that is less than 7 million years old. Unlike previous studies, we find no correlation between genome size and latitude, but do uncover a significant relationship between genome size and body length. Further, we find that the proportion of repetitive content predicts genome size, and that the largest genomes appear to be driven by expansions of LINE elements. Finally, we find evidence of genomic purging and body size reduction in two lineages that have independently colonized warm brackish waters, possibly indicating a strong physiological constraint of transitioning from surf-swept beaches to protected bays.Significance StatementThe evolution of genome size has been a long-standing puzzle in biology. In this work, we find that genome sizes may be driven by different selection regimes following shifts to a new habitat. Dramatic genome size changes can occur rapidly, in only a few million years.Data Availability StatementRaw data sheets have been deposited on Dryad: SUBMITTED. Raw sequence reads are available at from NCBI under Bioproject SUBMITTED.

Dramatic genome size variation exists across the Tree of Life. Some crustacean groups, such as amphipods, have genome sizes that correlate with body size, temperature, and water depth, indicating that genome sizes may be constrained due to physiological pressures. This may indicate that a general “genome-temperature-size” rule exists in ectotherms, in which body-size and latitude may be predictive of genome size. We examined the relationship between genome size, repetitive content, and environmental variables on a clade of sand-burrowing amphipods (Haustoriidae) that are distributed across the Gulf of Mexico and the North Atlantic. We uncovered a 6-fold genome size variation within Haustoriidae, a substantial amount considering this clade is less than 7 million years old. Unlike previous studies, we find no correlation between genome size and latitude, but do uncover a significant relationship between genome size and body length. Further, we find that the proportion of repetitive content predicts genome size, and that the largest genomes appear to be driven by expansions of LINE elements. We also found evidence of genomic purging and body size reduction in two lineages that have independently colonized warm brackish waters, possibly indicating a strong physiological constraint of transitioning from surf-swept beaches to protected bays.

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The eye is a vital organ not only in terms of vision but also being an important component of facial expression [1]. Loss or absence of a part of the face especially eye can cause severe physical and emotional problems [2]. Loss of eye could be because of different eye diseases, malignancies, congenital defect, trauma, chemical injuries, painful blind eye or sympathetic ophthalmia [3].Several stock ocular prosthesis are readily available in the market but Custom-made ocular prosthesis has many advantages and looks realistic. The complaint like discharge, itchiness, redness is more in stock eye prosthesis. Cosmetically compromising and movement is less due to improper fitting, shape and size. Impression taking in the custom-made eye prosthesis plays the vital role in shape, size of ocular prosthesis and comfortability of the patient while wearing it. Custom made ocular prosthesis provides better fit and improved exquisite, but they are more time-consuming and needs more patience and expertise [5]. This case report demonstrates innovative technique for fabricating custom ocular prosthesis with manual scleral and iris painting using coloured pigments which provides delicately satisfactory result long lasting with comfortable and better fit.