Pb binds with greater affinity, but is that good? calmodulin is generally though to be regulated by changes in calcium levels. higher affinity cation could inhibit that function, no?

That interpretation of the historical data goes counter to the authors view that the lead levels may be anecdotal due to location of a lead mine, and lead levels were not found in an individual from a different site.

"Periods of lead exposure during the childhoods of these two French Neanderthals are remarkable, as biogenic lead bands were not apparent in the ~100-ka-old Belgian individual discussed above, and decades of research have shown that there is no safe level for lead in humans and other animals."