Black Walnut Tree Trivia Black Walnuts, Juglans nigra, grow mainly in the Eastern and Central United States but they occur in moderate numbers nearly everywhere in the U.S. east of the Great Plains, except for New England and south Florida. They grow up to 150 feet with long, straight trunks up to a yard in diameter.
In the 1970s, a gene related to how our brain grows our limbs was given the name âhedgehogâ in relation to the spiky appearance of fruit flies with a defective version of the gene.In 1995, three strains of the âhedgehogâ gene were found and named âDesert-Hedgehogâ, âIndian-Hedgehogâ, and amusingly, âSonic-Hedgehogâ.onic Hedgehog Homolog (SHH) is one of three proteins in the mammalian hedgehog family, the others being desert hedgehog (DHH) and Indian hedgehog (IHH). SHH is the best studied ligand of the hedgehog signaling pathway.
Both the gene and the protein may also be found notated alternatively as  Shh . Sonic hedgehog is one of three proteins in the mammalian signaling pathway family called hedgehog, the others being desert hedgehog (DHH) and Indian hedgehog (IHH).SHH is the best studied ligand of the hedgehog signaling pathway.onic hedgehog is one of three proteins in the mammalian signaling pathway family called hedgehog, the others being desert hedgehog (DHH) and Indian hedgehog (IHH).