My favorite aquatic birds are the grebes (Podicipedidae). When you get the opportunity, it’s always an exciting moment observing in its natural habitat an individual diving and hunting or a family being together. 

During the Late Miocene (Tortonian age, roughly 11-7 milion years ago) large part of Eastern Europe was covered by a megalake (a remnant of the inland sea) called the Paratethys. There, among others, numerous species existed that would be superficially recognizable today. These were waterfowl, loons, grebes, cormorants, turtles, seals and even pygmy whales.

One of the birds found in this locality is the grebe Podiceps miocenicus. Judging from the broken humerus preserved, it was similar to the crested grebe (Podiceps cristatus) but somewhat larger in size.

References:

• Noi contribuţii privind studiul avifaunelor din Paratethys
• https://www.science.org/content/article/rise-and-fall-world-s-largest-lake?