The site at Gobekli Tepe, or "Potbelly Hill," on the Urfa plain in southeastern Turkey is believed by some to be the world's first place of worship. This would upend the conventional thought that religion developed as a byproduct of human settlements. Vincent J. Musi/National Geographic Society/Corbis hide caption

itoggle caption Vincent J. Musi/National Geographic Society/Corbis

Israeli Defense Minister Moshe Ya'alon delivers a statement at the Israel Defense Forces headquarters in Jerusalem in June. Thomas Coex/AFP/Getty Images hide caption

itoggle caption Thomas Coex/AFP/Getty Images

Peshmerga look out from a front-line outpost — a few sandbags, soldiers, and grenades perched on the brow of a hill — to the eastern Iraqi town of Jalula. The Kurdish fighters are grappling with how to combat changing ISIS tactics. Alice Fordham/NPR hide caption

itoggle caption Alice Fordham/NPR

Adi Asulin stands in the kitchen of her family's remodeled apartment north of Tel Aviv. She saved thousands of dollars by flying to China to buy furnishings and flooring directly from manufacturers. Emily Harris/NPR hide caption

itoggle caption Emily Harris/NPR

Syrian Kurdish fighter Delkhwaz Sheikh Ahmad, 22, sits with his wife Siham, 23, and their two sons, Dilyar and Ibrahim, at his brother's house on the Turkey-Syria border on Friday. He was preparing to leave for Kobani, Syria, to rejoin the fighting against the Islamic State. Lefteris Pitarakis/ASSOCIATED PRESS hide caption

itoggle caption Lefteris Pitarakis/ASSOCIATED PRESS

Aza Betwata (left) and his brother Mirwan (center) left Holland to join the Kurdish peshmerga fighting against ISIS militants in northern Iraq. Though the brothers come from a family of fighters, Aza had just two days of training — his brother must show him how to strip and clean his rifle. Alice Fordham/NPR hide caption

itoggle caption Alice Fordham/NPR

A family passes through Maktab Khaled in northern Iraq, the last Kurdish checkpoint before they make their way to Kirkuk. ISIS-controlled territory lies less than a mile away. Leila Fadel/NPR hide caption

itoggle caption Leila Fadel/NPR