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59 free Hard Nature trivia questions with answers — nature quiz, new questions added Aug 2026.
This hard nature trivia quiz is for people who already know the cheetah is fast and the blue whale is big. It asks how many types of photoreceptor a mantis shrimp packs into each eye, what temperature a lightning channel reaches, which lake holds a fifth of the planet's fresh surface water, how many eyes a box jellyfish has, where the wettest place on Earth is, and which tree has been alive since before the pyramids. Animals, plants, fungi, oceans, deserts, volcanoes and weather all get a turn. It suits pub quiz setters who need a genuinely difficult round, science teachers looking for stretch questions, and anyone who found our main nature trivia too gentle. Expect most questions in the hard-to-expert range, with a few medium ones so nobody scores zero. Every answer has been checked against the Wikipedia article on the species, place or phenomenon, and each question shows its source once you have answered.
30 of 59 questions with answers and explanations. Play the quiz
Q 01Humans have four types of photoreceptor cell. How many does a mantis shrimp have?
Between 12 and 16
Their clubs also strike with an acceleration of about 10,400 g, fast enough to boil the water around them into cavitation bubbles.
Q 02To what temperature does the air around a lightning flash heat?
About 30,000 °C
A lightning channel heats the surrounding air to about 30,000 °C, roughly five times the Sun's surface temperature; the explosive expansion of that air is thunder.
Q 03Tardigrades in their dormant state have survived temperatures as low as what?
−272 °C
Dormant tardigrades have survived −272 °C, about one degree above absolute zero, and have also survived the vacuum and radiation of open space.
Q 04Who first described tardigrades in 1773, calling them "little water bear"?
Johann August Ephraim Goeze
Johann August Ephraim Goeze described them in 1773 as 'kleiner Wasserbär', little water bear; Lazzaro Spallanzani supplied the name Tardigrada, slow walkers, three years later.
Q 05Which bristlecone pine, felled on Wheeler Peak in 1964, proved to be about 4,900 years old?
Prometheus
Prometheus, a Great Basin bristlecone pine on Wheeler Peak, Nevada, was cut down in 1964 by a graduate student; its rings showed it was at least 4,862 years old.
Q 06Pando, the quaking aspen clone in Utah's Fishlake National Forest, has roughly how many stems?
47,000
Pando has roughly 47,000 genetically identical stems sharing one root system across about 43 hectares, with an estimated mass of around 6,000 tonnes.
Q 07Oregon's Armillaria ostoyae "humongous fungus" covers about how much ground?
3.5 square miles
The Malheur National Forest Armillaria ostoyae spans about 3.5 square miles, roughly 2,400 acres, and may weigh up to 35,000 tons, making it a candidate for the largest organism by area.
Q 08Which desert plant grows only two leaves in its entire life, which can last over a thousand years?
Welwitschia
Welwitschia mirabilis of the Namib Desert grows only two leaves from a woody crown; they keep growing for a life that can exceed a thousand years, shredding into ribbons in the wind.
Q 09Wolffia microscopica, the fastest-growing flowering plant, doubles in about how long?
29.3 hours
Wolffia microscopica doubles its biomass in about 29.3 hours, the fastest recorded for any flowering plant; these watermeals are also the smallest flowering plants, like specks of cornmeal on a pond.
Q 10A Venus flytrap shuts fully only if a second trigger hair is touched within about how long?
Twenty seconds
A second trigger-hair touch within about twenty seconds is needed to close the trap; the double-touch rule stops the Venus flytrap wasting energy on raindrops and debris.
Q 11Lake Baikal, 1,642 m deep, holds roughly what share of the world's fresh surface water?
22–23%
Baikal holds about 22–23% of the world's fresh surface water, more than all the North American Great Lakes combined, and at 25–30 million years old it is the oldest lake.
Q 12What is the maximum known depth of the Challenger Deep in the Mariana Trench?
10,935 m
Its floor is more than 2 km farther from sea level than the summit of Everest is above it.
Q 13Angel Falls in Venezuela, the tallest uninterrupted waterfall, has a total height of what?
979 m
Angel Falls drops 979 m in total, with an uninterrupted main plunge of 807 m; its Pemon name is Kerepakupai Vená.
Q 21Old Faithful erupts on average about every how many minutes?
92
Old Faithful erupts on average about every 92 minutes, with intervals between roughly 44 and 125 minutes; the 1870 Washburn–Langford–Doane Expedition named it.
Q 22Which island emerged in 1927 from the caldera left by the 1883 eruption in the Sunda Strait?
Anak Krakatoa
Anak Krakatoa, 'Child of Krakatoa', first broke the surface in 1927 inside the 1883 caldera; Rakata is the only surviving remnant of the original island.
Q 23What height did the joint Nepalese–Chinese survey publish for Everest in 2020?
8,848.86 m
The joint survey announced 8,848.86 m in December 2020, measured to the snow cap; China's 2005 rock-height figure had been 8,844.43 m.
Q 14In 2025, the surface of the Dead Sea sat roughly how far below sea level?
About 440 m
In 2025 the Dead Sea surface lay about 440 m below sea level, the lowest land point on Earth; its 34% salinity is about 9.6 times the ocean's, and the level drops roughly a metre a year.
Q 15The Caspian Sea, the largest inland body of water, has a salinity of about what?
1.2%
Caspian water averages about 1.2% salinity, roughly a third of seawater's 3.5%, which is one reason it is argued over as both a lake and a sea.
Q 16Which Meghalaya village is reportedly the wettest place on Earth, with about 11,872 mm of rain a year?
Mawsynram
Mawsynram averages about 11,872 mm of rain a year; it sits about 15 km west of Cherrapunji, which long held the title in every schoolbook.
Q 17Earth's lowest reliably measured temperature, −89.2 °C, was recorded at which Antarctic base?
Vostok
Vostok Station, founded by the Soviet Union in 1957, logged −89.2 °C on 21 July 1983; it sits at the southern Pole of Cold and sees no sun in polar night.
Q 18On what date was the record 134 °F (56.7 °C) air temperature measured at Furnace Creek, Death Valley?
10 July 1913
The 134 °F reading came on 10 July 1913; the highest reliable modern readings at Furnace Creek are 130 °F, reached in August 2020 and July 2021.
Q 19The Atacama Desert averages roughly how much rain per year?
About 15 mm
The Atacama averages about 15 mm of rain a year; it lies in a two-sided rain shadow between the Andes and the Chilean Coast Range, and some stations have never recorded rain.
Q 20The most recent Yellowstone supereruption, which created the present caldera, was how long ago?
640,000 years
The Lava Creek eruption about 640,000 years ago formed the present caldera; the first and largest cycle, 2.08 million years ago, produced the Huckleberry Ridge Tuff and the Island Park Caldera.
Q 24Roughly how many individual trees are estimated to stand in the Amazon rainforest?
390 billion
A 2013 estimate put the Amazon at about 390 billion individual trees belonging to roughly 16,000 species; about 60% of the forest lies in Brazil.
Q 25Which two deserts cover more area than the Sahara?
Antarctica and the Arctic
Antarctica and the Arctic are the two largest deserts; a desert is defined by low precipitation, not heat, and the polar regions receive very little.
Q 26Which animal produces the loudest sound of any creature, with clicks reaching 236 decibels underwater?
Sperm whale
Sperm whale echolocation clicks have been measured at 236 decibels, the loudest sound any animal makes; the species also has the largest brain, over five times a human's by weight.
Q 27The heart of a stranded North Atlantic blue whale, the largest known in any animal, weighed how much?
180 kg
The heart, from a blue whale stranded in Newfoundland in 2014 and preserved by the Royal Ontario Museum, weighed about 180 kg; the animal itself can reach 30 m and 190 tonnes.
Q 28The colossal squid's eyes, the largest of any known creature, measure at least what across?
27–30 cm
Colossal squid eyes measure 27–30 cm across, the largest of any known animal; the species is also the heaviest invertebrate, with a confirmed 495 kg specimen.
Q 29Greenland sharks reach sexual maturity at roughly what age?
Around 150 years
Females mature at around 150 years; the oldest individual in the 2016 eye-lens study was estimated at 392 years, plus or minus 120, the longest-lived vertebrate known.
Q 30Which mammal may be the longest-lived of all, with individuals exceeding 200 years?
Bowhead whale
Bowhead whales can live past 200 years, one individual estimated at 211; old stone harpoon points recovered from living bowheads back up the age estimates.