Behaviour: Mammals category. Giant Gathering by Tony Wu, USA. Dozens of sperm whales mingled noisily off Sri Lanka’s northeast coast, stacked as far down as Tony could see. This was a congregation of dozens of social units, like a gathering of the clans. Aggregations like this could be a critical part of the whales’ rich social lives but are rarely reported. Some two thirds of the population was wiped out before commercial whaling was banned in 1986. This kind of major gathering could be “a sign that populations are recovering”, says Tony. (Photo by Tony Wu/Wildlife Photographer of the Year 2017)

An Egyptian man shows off his motorcycle skills, following the outbreak of the coronavirus disease (COVID-19), in Cairo, Egypt on July 17, 2020. (Photo by Mohamed Abd El Ghany/Reuters)

A camel is seen in front of the pyramids, which is one of the seven wonders of the world that was visited by 14.9 million tourists last year in Giza, Egypt on February 21, 2024. The pyramids were named after the tombs of fathers, sons and grandsons, including the largest pyramid Cheops (King Khufu), the middle pyramid Khafre (King Khafre) and the small pyramid Menkaure (King Menkaure). (Photo by Utku Ucrak/Anadolu via Getty Images)

A model wears a creation for the Louis Vuitton Spring/Summer 2024 womenswear fashion collection presented Monday, October 2, 2023 in Paris. (Photo by Vianney Le Caer/AP Photo)

The Queen Mary 2 is saluted by the HMB Endeavour, the replica of Captain James Cook's ship, on March 4, 2012 off the coast of Victoria, Australia. (Photo by James Morgan/Carnival Australia via Getty Images)

Miranda Kerr poses at the David Jones Spring/Summer fashion preview on Burke Street on August 10, 2011 in Melbourne, Australia. (Photo by Lucas Dawson)

There are many types of collections. Some are formed by purposefully collecting certain objects, such as stamps or coins. However, some collections are only a byproduct of an obsession, a quirk of mind. For example, Paul Brockmann got into the habit of buying his girlfriend and later his wife a dress every time they went ballroom dancing. It might seem excessive to some, but it was his way of showing his affection. Overtime, this collection grew to be enormous, counting 55,000 dresses in total. Basic math tells us that either they went ballroom dancing three times per day for every day of their lives, or he bought them in huge bundles every time.

An Emirati child plays with an airplane model near the venue of the Mazayin Dhafra Camel Festival, on December 20, 2012 near the city of Madinat Zayed, 150 kms west of Abu Dhabi. The festival, which attracts participants from around the Gulf region, includes a camel beauty contest, a display of UAE handcrafts and other activities aimed at promoting the country's folklore. (Photo by Karim Sahib/AFP Photo)