If giraffes grew their necks longer with sheer will power (as Lamarck hypothesized), they would still have had to deal with a slew of anatomical challenges. Thankfully, natural selection accrued some necessary adaptations to help them meet these challenges. This includes, high bone density to support their incredible stature, high systemic blood pressure and high BP tolerance to supply blood to their brains way up in the clouds.
A group of researchers led by Chang Liu, identified several mutations in the giraffe genome that produce these physiological adaptations. One particular gene with a high number of unique mutations was inserted into mice genome using CRISPR–Cas9.
Gene-edited mice with the giraffe gene (FGFRL1) showed high hypertension resistance and bone mineral density, suggesting that the mutant gene plays an important role in conferring these adaptations. The study also provides insights into molecular mechanisms of behavioral adaptations like hyper-vigilance.
Read more about the study here.
