1.8 million years ago, giant German hippopotamuses wallowed on the banks of the Elbe.
Hippos were all over Europe then, along with other megafauna like woolly mammoths and giant cave bears. What went wrong? Palaeontologists blame global cooling during the Pleistocene Era, which may have forced Europe’s hippos to shrink to pygmy sizes before finally driving them to warmer climes.
Hippos were a constant feature of European wildlife for about 1.4 million years, all through the climatically turbulent time of the Pleistocene era, which witnessed 17 glacial events. The experience of such environmental changes would not have been without cost. Lead author Dr. Paul Mazza and co-author Dr. Adele Bertini from the University of Florence investigated the impact this global cooling may have incurred.
Their research focused on fossils from across Europe, ranging from the German town of Untermaßfeld in Thuringia, to Castel di Guido, North of Rome, and Collecurti and Colle Lepre in Italy’s Central Eastern Marche province. The fossils were compared to a database of measurements taken from modern African and fossil European hippos.
“The German fossil from Untermaßfeld is the largest hippo ever found in Europe, estimated to weigh up to 3.5 tonnes,” said Mazza. “The Collecurti specimen was also large, but interestingly even though it was close in both time and distance to the Colle Lepre specimen the latter specimen was 25% smaller. A final specimen, an old female from Ortona in central Italy, was smaller again. It was 17% smaller than the Collecurti fossil and approximately 50% lighter.”
The team found that a clear size threshold separated hippo specimens which heralded from different parts of the Pleistocene age. The hippos from the early Pleistocene were the largest ever known while smaller specimens emerged during the middle Pleistocene. Larger specimens briefly reappeared during the late Pleistocene.
“We believe the size difference was connected to the changing environmental conditions throughout the Pleistocene,” said Mazza. “The Ortona hippo, the smallest of the specimens, lived in a climate where glacial cycles turned colder, while cold steppes replaced warm ones across the Mediterranean.”
The drop in temperature and rainfall during the Pleistocene caused significant changes to plant life across Europe resulting in an expansion of grassy steppes. Being grazers hippos may have been expected to thrive in this new environment. Unexpectedly they appeared to shrink, only re-attaining their past size during the warm periods of the late Pleistocene, when forests and woodland re-colonised the steppes.
During their time in Europe hippos were forced to live in habitats influenced by a general environmental trend towards cooler and drier conditions. In response hippos achieved giant sizes during warmer and relatively more humid stages, but became smaller, and even very small, under non-ideal environmental conditions.
“While hippos are normally considered indicators of warm, temperate habitats this research shows that temperature was not only the controlling factor for their ancient ancestors,” concluded Mazza. “Our research suggests other factors, such as food availability, were equally important. Appreciating the importance of factors beyond temperature is of great significance as we consider how species may adapt to future ecological and environmental changes.”
Citation: Mazza. P, Bertini. A, “Were Pleistocene hippopotamuses exposed to climate-driven body size changes?” Boreas, Wiley, October 2012, DOI: 10.1111/j.1502-3885.2012.00285.x
- PHYSICAL SCIENCES
- EARTH SCIENCES
- LIFE SCIENCES
- SOCIAL SCIENCES
Subscribe to the newsletter
Stay in touch with the scientific world!
Know Science And Want To Write?
- On Sexuality, You Weren't Born That Way, Says Paper
- Bubble-wrapped Sponge Creates Steam Using Sunlight
- Anomaly!: Book News And A Clip
- Reframing Body Weight As Baby Weight May Help Women Handle Pregnancy
- Beekeeping Fad And The Stress Of Traveling Is Harmful To Bees
- Petition: Let's End Dramatized Reporting Of "Doomsday" Stories - The Vulnerable Get Suicidal
- Stem Cell Therapy Heals Injured Mouse Brain
- "i've often wondered https://en.wikipedia.org/wiki/Behavioral_sink ..."
- "Dylan, yes back online now. The Sun, and Moon are visible in all those places, of course, so if..."
- "Tina, I think it's best to try to understand the constellation argument because then you can just..."
- "People worry about a system entering ours and spelling doomsday for us all, however I believe if..."
- " I appreciate your hard work and look forward to any future publications with great interest, thank..."
- If Facebook Is Guessing Your Politics, You’re Probably Safe From Being Pigeon-Holed
- Pregnancy-Related Deaths Rising, But Why?
- Fauci: Don’t Make Policy Based on Animal Studies
- Exercise Could Save Your Liver
- Precision Medicine Stands On Imprecise Infrastructure
- Standing with Giants: A Collection of Public Health Essays in Memoriam to Dr. Elizabeth M. Whelan
- Who is Stalking you on Facebook? Who is your biggest Fan? (Updated Methods).
- Who Is Stalking You On Facebook? Who Is Your Biggest Fan?
- On Sexuality, You Weren't Born That Way, Says Paper
- How A Former Naturopath Can Help Unravel The Trickery of Alternative Medicine
- No, There Isn't A Planet Called Nibiru, Soon To Hit Earth, And Often Visible In Your Photos Of The Sun :)