Should I reglue mahogany table splitting at joints?

I have a 4ft x 8ft x 2.5 inch thick mahogany dining table made from glued-together planks each about 6 inches wide. At each end of the table, a crack has appeared, 6 inches long on one end, and about 2 feet long on the other side. The cracks are about 2mm wide each. The table was made in Africa 4 years ago and has survived four Canadian winters. I suspect it is the dry air in winter that has warped the wood. Should I assume summer humidity will make it go back to how it was, or should I try to glue and clamp it? Thanks in advance for any advice.