Chapman's Baobab, claimed to be the largest tree in Africa at 25 metres around, camped under and measured by early explorers Chapman, Baines, Livingstone and others. Makgadikgadi Pans National Park, Botswana, Africa

Chapman's Baobab, claimed to be the largest tree in Africa at 25 metres around, camped under and measured by early explorers Chapman, Baines, Livingstone and others. Makgadikgadi Pans National Park, Botswana, Africa

Loggerhead Turtle (Caretta caretta) being measured prior to tagging. Azores

Asian girl having height measured on wall

Asian boy having height measured on wall

Particulate matter monitoring station, spot station, at Neckartor, B14, Cannstatter Strasse street, the highest PM levels nationwide are regularly measured in downtown Stuttgart, Baden-Wuerttemberg, Germany, Europe

People view the world's tallest snowman, actually a snow woman named after US Senator Olympia Snowe. The Guinness Book of World Record snowman, built the winter of 2007-08, in Bethel Maine, measured 122 feet tall, and used an estimated 13 million pounds of snow.

High Mountain Rangers Tom Ditola and David Weber are taking a rest on the West Rib on Mount McKinley, Alaska. Mount Hunter in the background. They are above the clouds in blue sky and the sun is shining. Mount McKinley, native name Denali, is the highest mountain peak in North America, with a summit elevation of 20,321 feet (6,194 m) above sea level. At some 18,000 feet (5,500 m), the base-to-peak rise is considered the largest of any mountain situated entirely above sea level. Measured by topographic prominence, it is the third most prominent peak after Mount Everest and Aconcagua. Located in the Alaska Range in the interior of the U.S. state of Alaska, McKinley is the centerpiece of Denali National Park and Preserve. Every climbing season High Mountain Rangers of the Denali National Park Service are called to help climbers in need. If possible the patient is brought down to base camp on foot, only in life threatening conditions a helicopter is called to evacuate the patient to a hospital in Anchorage.

Mountain ranger Brian Scheele on this way to Windy Corner on Mount McKinley, also know as Denali, in Alaska. He is pulling a sled, that together with his heavy backpack is containing all the gear like tents, clothing and food. Every climbing season High Mountain Rangers of the Denali National Park Service are called to help climbers in need. If possible the patient is brought down to Basecamp on foot, only in life threatening conditions a helicopter is called to evacuate the patient to a hospital in Anchorage. Mount McKinley, native name Denali, is the highest mountain peak in North America, with a summit elevation of 20,321 feet (6,194 m) above sea level. At some 18,000 feet (5,500 m), the base-to-peak rise is considered the largest of any mountain situated entirely above sea level. Measured by topographic prominence, it is the third most prominent peak after Mount Everest and Aconcagua. Located in the Alaska Range in the interior of the U.S. state of Alaska, McKinley is the centerpiece of Denali National Park and Preserve.

People view the world's tallest snowman, actually a snow woman named after US Senator Olympia Snowe. The Guinness Book of World Record snowman, built the winter of 2007-08, in Bethel Maine, measured 122 feet tall, and used an estimated 13 million pounds of snow.

A sea urchin is measured onboard a dive boat in San Diego, Ca. According to many, the best urchins - the big Pacific Reds - come from the kelp forests off Point Loma, Ca., thousands of miles from countries that pay the big money for fresh urchin roe.

Tek (Trimix) speleologist diver in a karstic underwater cave over 70 meters deep, Photogrammetry, twiglight zone, Mayotte

Installation of an acoustic recorder for the study of the frequentation and impact of acoustic diving, in the Natural Marine Reserve of Cerbere-Banyuls, Pyrenees-Orientales, Occitania, France

Instrument for measuring soil humidity at research station ?La Selva? in Puerto Viejo de Sarapiqui, Costa Rica

Researcher measuring a 2.6 gram Stripe-throated Hermit hummingbird wing as part of a pollination study, rainforest at the "La Selva" research station in Puerto Viejo de Sarapiqui, Costa Rica

Researcher measuring the beak of a Rufous-tailed hummingbird as part of a pollination study, rainforest at the "La Selva" research station in Puerto Viejo de Sarapiqui, Costa Rica

European pond turtle (Emys orbicularis) Measurement and weighing of a , Brenne, France

European pond turtle (Emys orbicularis) Measurement and weighing of a , Brenne, France

CBD producer or cannabiculturist (cannabidiol) checking temperature and hygrometry in a container where are located its reproductive plants lit by sodium lamps 18 hours a day, Montagny, France

European pond turtle (Emys orbicularis) Measurement and weighing of a , Brenne, France