Extended Data Figure 3:
A 4-way model for the entire Dnipro-Don-Volga-Caucasus region. Error bars show ±1 standard error.
Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.