In Case You Missed It: The Week of May 20-26

* Republican-led Ohio legislature passes bill establishing energy fracking rules.

* Climate scientists say warming could exceed the dangerous 3.5 C threshold. 

* Indian state legalizes the shooting of tiger poachers on sight.

* China files a complaint with the WTO against five U.S. states regarding solar subsidies.

* The battle over labeling genetically modified food in the U.S. has heated up over the last year.

* The Brazilian president has vetoed portions of a controversial bill that aims to open up more of the Amazon to deforestation.

* Nebraskan citizens fight back over Keystone Pipeline eminent domain.

* Does algae-derived biofuel have promise?