Coronal and ventral x-rays of the hammerhead shark, Sphyrna mokarran.
The distinguishing feature of this animal is, of course, the highly unusual skull shape. You may once have wondered what exactly this seemingly clumsy structure contributes to this fearsome predator, and biologists still do. However, a number of theories exist to explain this unique adaptation; here are some of the best:
All the better to see you with: mounting the eyes at either end of the broad skull allows excellent vision in all areas of the vertical plane. Hammerhead sharks, as hunters of bottom-dwelling animals, can use this superior angle of vision to better locate prey.
Another pair of fins. The head has evolved into the shape of an effective hydrofoil. It is thought that this may provide greater stability to the shark when making sharp turns and hunting.
Heartbeat sensor. Like many sharks, the hammerhead possesses specialised electrosensory organs called the ampullae of Lorenzini. With these, it can detect the magnetic activity of the Earth and find its heading by means of biological compass. Much more impressively, the hammerhead can detect the minuscule electrical activity emitted by the muscle contractions of its prey, allowing location even when hidden from sight. Almost like a skull-mounted metal detector, the shark may sweep the seabed. All it takes is a heartbeat to give the game away.
The Royal Greenhouses of Laeken (Dutch: Koninklijke Serres van Laken, French: Serres Royales de Laeken), are a vast complex of monumental heated greenhouses in the park of the Royal Palace of Laeken in the north of Brussels. It is one of the major tourist attractions of the city.
The complex was commissioned by King Leopold II and designed by Alphonse Balat. Built between 1874 and 1895, the complex was finished with the completion of the so-called “Iron Church”, a domed greenhouse that would originally serve as the royal chapel. The total floor surface of this immense complex is 2.5 hectares (270,000 square feet). 800,000 liters (over 200,000 US gallons) of fuel oil are needed each year to heat the buildings.
The complex can only be visited during a two-week period in April–May each year, when most flowers are in full bloom.