“The Challenge!” Young boy relishes in a game of tug of war before school. Photo location: Lake Titicaca, Peru. (Photo and caption by Paul Heyman/National Geographic Photo Contest)

In this May 31, 2016 photo, pieces of watermelon litter the trash area of the Coche public market in Caracas, Venezuela. Staples such as corn flour and cooking oil are subsidized, costing pennies at the strongest of two official exchange rates. But fruit and vegetables have become an unaffordable luxury for many Venezuelan families. (Photo by Fernando Llano/AP Photo)

Family Donation by Si Thu Ye Myint (Myanmar, Winner). Myin Twin village in upper Myanmar. (Photo by Si Thu Ye Myint/Sony World Photography)

Yak near Yamdrok lake, Tibet. It is a long-haired bovinae found throughout the Himalayan region of south Central Asia, the Tibetan Plateau and as far north as Mongolia and Russia. The Tibetan economy is dominated by subsistence agriculture. Due to limited arable land, the primary occupation of the Tibetan Plateau is raising livestock, such as sheep, cattle, goats, camels, yaks, dzo, and horses. The Tibetan yak is an integral part of Tibetan life. (Photo by Dennis Jarvis)

“Scott Linstead is an internationally published, freelance wildlife photographer/writer. His clients include Natural History Magazine, Hewlett Packard, Ranger Rick Magazine and a number of wildlife publications in North America and Europe. Scott's column on the techniques of bird photography appears in every issue of Outdoor Photography Canada”.

Photo: A veiled chameleon extends its tongue to catch a cricket. Canadian wildlife photographer Scott Linstead, formerly an aerospace engineer and high school teacher, uses a device called Phototrap “to not only photograph the elusive, but also the unimaginably quick”. (Photo by Scott Linstead)

These beautiful images aim to show the more artistic side of Hawaii’s recent volcano eruption, highlighting the sheer power of Mother Nature and the act of creating new land. Photographer CJ Kale’s breathtaking works show the molten lava in its incredible vibrancy, whether it’s bursting from the ground in fireworks fashion or pouring into surrounding waters, causing steam to rise. (Photo by CJ Kale/Caters News Agency)

These adorable pawtraits seem to show the personalities of a variety of canines, capturing their incredible diverseness in their expressions and fine details. Khokhlov and Ershova, who are from Moscow, have taken portraits of about 50 breeds of pooches – earning much critical acclaim. (Photo by Alexander Khokhlov/Veronica Ershova/Caters News Agency)

This month’s selection of travel imagery mixes quiet moments and superlative views. The overall 2018 prize is a West Greenland trip with Wild Photography Holidays. Here: “This was taken on a safari in Kruger national park, South Africa. The scene was like something straight out of a storybook: a wild baboon, impala and elephant crossing the road together, all lined up neatly in a row”. (Photo by Will Clarke/The Guardian)