Plot.plot({
marks: [
Plot.frame(),
Plot.dot(salamanders, {x: "totalLength",
y: d => d.weight,
opacity: 0.5,
fill: "totalLength",
r: "totalLength",
sort: {channel: "fill"},
tip: true})
],
y: {type: "pow", exponent: 0.5},
x: {domain: [0, 400], ticks: 5, reverse: true},
color: {range: ["cyan", "purple"], legend: true},
grid: true
})