Markus and Mo weighed about 70kg (11st) at birth, and now weigh about 500kg (78st) each.
Rhino siblings celebrate first birthday with cake

Original reporting
BBC Science: read the full reportRelated stories

'Fascinating' rare beetle found in Wales again after 60 years
It was feared The Short-Necked Oil Beetle had become extinct in Wales after recent surveys

Oil tank vandalism results in waterfowl park 'nightmare'
The popular attraction in County Down has been forced to close while efforts continue to remove oil from the pond.

'Rok' solid recognition for Slovenian space scientist
Two men from the Armagh Planetarium and Observatory have had asteroids named in their honour in recognition of their work.

Rare damselfly spotted by restored chalk river
The Herts and Middlesex Trust says it is "thrilled" the new wetlands are helping species thrive.
Scientists say a forgotten particle may explain why the universe exists
A mysterious particle overlooked for decades may hold the key to why matter survived the Big Bang, allowing stars, planets, and life to exist. Scientists believe this forgotten neutrino reshaped the early universe and may have left detectable gravitational wave signals that could help unlock the cosmos’s deepest mysteries.
Scientists discover the hidden “muscles” trees use to straighten themselves
Scientists have discovered that trees can sense their own shape and straighten their trunks using specialized wood that acts like opposing muscles. This remarkable ability helps trees maintain their posture and could lead to stronger forests, better timber, and more resilient crops.