Climate Change May Be Causing Birds to Shrink-and Their Wings to Grow

In 1978, David Willard, an ornithologist at the Field Museum in Chicago, began collecting birds that had died after colliding with large windows—a fate that befalls up to one billion birds each year. Over the decades, Willard worked with volunteers from the Chicago Bird Collision Monitors during the spring and fall migration seasons to assemble a collection of more than 100,000 specimens. He kept meticulous measurements of the dead creatures, with the goal of tracking seasonal trends.

In a new statistical analysis of this vast trove of data, Willard and his fellow researchers reveal an important trend that emerged among the specimens over time. Writing in the journal Ecology Letters, the team explains that the bodies of the birds in the Field Museum’s collections have gotten smaller, while their wingspans have increased in size—a morphological phenomenon that the scientists attribute to climate change.

https://www.smithsonianmag.com/smart-news/climate-change-may-be-causing-birds-shrinkand-their-wings-grow-180973701/?utm_source=smithsoniandaily&utm_medium=email&utm_campaign=20191205-daily-responsive&spMailingID=41272093&spUserID=NTkyNzY2ODg1MzgyS0&spJobID=1660501402&spReportId=MTY2MDUwMTQwMgS2