[gbil]

from the link

>The transmission technology will continue to be of great importance, as sensors weighing five grams are still too heavy for many animal species: 70 percent of bird species and 65 percent of mammal species, not to mention amphibians or insects, cannot be equipped with sensors using the current technology. The next generation of Icarus sensors will therefore weigh just one gram.

This is just amazing

[onychomys]

And the really bonkers thing about many birds is that the single gram will still be a sizeable fraction of their total body weight. Chickadees and nuthatches (and other birds of that size) weigh somewhere between 10 and 15 grams, usually. Zebra finches are about the same. It'll be a really long time before we can put sensors on those!