Alpenseen (Alpine Lakes) is a nature documentary that shows us the fascinating world of deep mountain lakes. Here we see many animals emerge from hibernation, and then catch a glimpse of what lies over one hundred meters below the surface.

Alpenseen (Alpine Lakes) is a nature documentary that shows us the fascinating world of deep mountain lakes. From the swiftly flowing streams to the cliffs high above, the area around the lakes hosts a number of different species.

Alpenseen (Alpine Lakes) is a nature documentary that shows us the fascinating world of deep mountain lakes. In this episode, we'll explore the mysterious "Lake of Blood" and some scandalous interspecies dating!

Alpenseen (Alpine Lakes) is a nature documentary that shows us the fascinating world of deep mountain lakes. In this part, we explore the mysterious "cow tracks" found throughout the Alps in stone. These are, in fact, ancient fossils from the time when this mountain range was an ocean floor.

Alpenseen (Alpine Lakes) is a nature documentary that shows us the fascinating world of deep mountain lakes. Here we see the female perch defending her spawn from North American crayfish, and look at the role of glaciers in storing Alpine water.

Alpenseen (Alpine Lakes) is a nature documentary that shows us the fascinating world of deep mountain lakes. Here we see the effects of global warming, from the melting ice on the mountains to the caves of Slovenia.

Alpine Lakes, a nature documentary, leads us into the fascinating world of deep mountain lakes. As snow covers the mountains, mammals and fish alike fight for survival.

Alpine Lakes, a nature documentary, leads us into the fascinating world of deep mountain lakes. When winter comes and the lakes freeze over, the fish under the thick ice cover have different ways of passing the time.

At the 9th Annual Conference of the German Council for Sustainable Development in Berlin on the 23rd of November 2009, Chancellor Angela Merkel talked about the upcoming challenges among others for the growth policy, for the educational and research policy, for species conservation and for international cooperation.

German chancellor Angela Merkel continues her talk at the German Council for Sustainable Development about sustainable ways of living and pleads for the importance of species diversity for us and our life on Earth.

At the end of the year 2011, the German Federal Chancellor Angela Merkel looks back upon the year's major natural, political and economic events. In her address, she encourages her fellow citizens to remain strong and resolute in the face of formidable challenges that lie ahead.

In the second part of her New Year's address, German chancellor Angela Merkel gives an overview of her policy goals for the coming year. She appeals to the citizens of Germany to join the discussion and work along side her in achieving those goals.

For owners of Apple computers, the honeymoon is now over! In comparison to PCs, the more expensive Apple computer was long considered safe from viruses and Trojan horses. Now one of the first Trojan horses has shown up in their devices. Copyright DPA

A fascinating video about some unusual archaeological finds in the Rhine-Main area, dating from the late Roman era.

In the second part of this video on the Frankfurt silver inscription, various experts explain why this find is so special.