Happy International Beaver Day!
These toothy, flat-tailed rodents are some of the greatest builders on earth, and, as some scientific research has shown us, they build for the long term.
We know this because of a map from one Lewis H. Morgan.
In the 1860s, he was working on a railroad development in the Upper Peninsula of Michigan when he came across a series of beaver building projects, including dams, which beavers use to create smaller, safer habitats for themselves and their fellow beavers, and the lodges in which they live.
Morgan found all this work so impressive that he began studying the beaver up close, and in 1868 he published a nearly 400 page book about the creatures and what they do.
Inside the book was a map of the area around what is now Ishpeming, Michigan, 48 square miles that included 64 beaver dams.
Jump ahead about a century and a half, when ecologist Carol Johnston came across that map in some postdoctoral research and started wondering whether any of those beaver builds were still in place.
So she compiled aerial imagery of the area to create a modern version of the old map and compared the two.
Of the 64 beaver sites Morgan included in his map, Johnston found that 46 – nearly three in four – were still intact as of 2018.
And the ones that were no longer on the map were in places where human engineers had changed the landscape themselves; without those changes, it’s possible the beavers’ work might have stayed up.
Some of the intact structures weren’t in top condition, which suggests that beavers aren’t always looking to use older dams or move into older houses.
But those that do can probably find one: in fact, there are lodges and dams even older than the ones on the Morgan map.
In one case, beavers were seen in 1850 using a dam that was first built in the year 520.
A 1,200 year old build? All we can say is, dam.
Today is also National Beer Day.
Beer has been brewed, sold, shared, enjoyed and sometimes over-enjoyed for pretty much all of recorded history.
There’s even a clay tablet from Mesopotamia, four thousand years ago, on which someone called Ur-Amma marks down that they received beer from Alulu the brewer.
Ur-Amma, by the way, said Alulu’s beer was “the best.”
Beaver Dams Can Last Centuries, 1868 Map Shows (Treehugger)
The Oldest Beer Receipt (Circa 2050 BC) (Open Culture)