60 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 60 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
Earth sees roughly 44 flashes every second, close to 1.4 billion a year.
Q 03Tardigrades in their dormant state have survived temperatures as low as what?
−272 °C
That is a single degree above absolute zero; they 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
Spallanzani supplied the name Tardigrada, meaning slow walkers, three years later.
Q 05How old was Methuselah, the bristlecone pine in California's White Mountains, in 2025?
4,858 years
At 4,858 years in 2025 it is the oldest known living non-clonal organism, already ancient when Stonehenge was finished.
Q 06Pando, the quaking aspen clone in Utah's Fishlake National Forest, has roughly how many stems?
47,000
Every stem is genetically identical and shares one root system covering about 43 hectares.
Q 07Oregon's Armillaria ostoyae "humongous fungus" covers about how much ground?
3.5 square miles
It may weigh 35,000 tons, making it a candidate for the largest living organism by mass, area and volume.
Q 08Which desert plant grows only two leaves in its entire life, which can last over a thousand years?
Welwitschia
The two leaves keep growing from a woody crown and shred into ribbons in the Namib wind.
Q 09Wolffia microscopica, the fastest-growing flowering plant, doubles in about how long?
29.3 hours
Wolffia are the watermeals, the smallest flowering plants on Earth, resembling 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
The double-touch rule stops the plant wasting energy closing on raindrops and debris.
Q 11Lake Baikal, 1,642 m deep, holds roughly what share of the world's fresh surface water?
22–23%
That is more than all the North American Great Lakes combined, and at 25–30 million years old it is also 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
The main plunge alone is 807 m; the Pemon name for the falls is Kerepakupai Vená.
Q 21Old Faithful erupts on average about every how many minutes?
92
It was named in 1870 by the Washburn–Langford–Doane Expedition and was the first geyser in Yellowstone to get a name.
Q 22Which island emerged in 1927 from the caldera left by the 1883 eruption in the Sunda Strait?
Anak Krakatoa
The name means Child of Krakatoa; Rakata is the only surviving remnant of the original island.
Q 23Everest's height was remeasured in 2020 by a joint Nepalese–Chinese survey. What figure did they publish?
8,848.86 m
Tenzing Norgay and Edmund Hillary made the first documented ascent in 1953 via the Southeast Ridge.
Q 14In 2025, the surface of the Dead Sea sat roughly how far below sea level?
About 440 m
Its 34% salinity makes it about 9.6 times saltier than the ocean, so swimmers simply float; the level keeps falling about a metre a year.
Q 15The Caspian Sea, the largest inland body of water, has a salinity of about what?
1.2%
That is roughly a third of average seawater, which is why 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
It sits just 15 km west of Cherrapunji, the place that used to hold the title in every schoolbook.
Q 17Earth's lowest reliably measured temperature, −89.2 °C, was recorded at which Antarctic base?
Vostok
The Soviet-founded station sits at the southern Pole of Cold and gets zero hours of sunshine in polar night months.
Q 18On what date was the record 134 °F (56.7 °C) air temperature measured at Furnace Creek, Death Valley?
10 July 1913
The highest reliable modern reading there is 130 °F, hit in both 2020 and 2021.
Q 19The Atacama Desert averages roughly how much rain per year?
About 15 mm
It sits in a two-sided rain shadow between the Andes and the Chilean Coast Range, and some stations there have never recorded rain.
Q 20The most recent Yellowstone supereruption, which created the present caldera, was how long ago?
640,000 years
It produced the Lava Creek Tuff; the first and largest cycle, 2.08 million years ago, formed the Island Park Caldera.
Q 24Roughly how many individual trees are estimated to stand in the Amazon rainforest?
390 billion
They belong to about 16,000 species, and 60% of the forest lies in Brazil.
Q 25The Sahara is the largest hot desert, but only the third-largest desert overall. Which two are bigger?
Antarctica and the Arctic
A desert is defined by precipitation, not heat, and the polar regions get very little.
Q 26Which animal produces the loudest sound of any creature, with clicks reaching 236 decibels underwater?
Sperm whale
It also has the largest brain on Earth, more than five times heavier than a human's.
Q 27The heart of a stranded North Atlantic blue whale, the largest known in any animal, weighed how much?
180 kg
The animal itself can reach about 30 m and 190–200 tonnes on a diet almost entirely of krill.
Q 28The colossal squid's eyes, the largest of any known creature, measure at least what across?
27–30 cm
It is also the largest living invertebrate at 495 kg confirmed, and it is the only cranchiid squid with hooks on its arms and tentacles.
Q 29Greenland sharks reach sexual maturity at roughly what age?
Around 150 years
The oldest individual was estimated at 392 years, plus or minus 120, making it the longest-lived vertebrate known.
Q 30Which mammal may be the longest-lived of all, with individuals exceeding 200 years?
Bowhead whale
Old stone harpoon points have been recovered from living bowheads, backing up the age estimates.