Glucocorticoids increase bone ; high levels of serotonin lead to bone density.

The glucocortocoids has the ability of increasing the bone loss while having a composition of serotonin in high levels will likely have the bone density to be at its low level. To complete the sentence; Glucocorticoids increase bone loss; high levels of serotonin lead to low bone density.

amber has allowed scientists to study dna that has been preserved over millions of years.