Whether you did or didn’t see this week’s Geminid meteor shower … you’ll enjoy these stunning images of the shower, from around the world. Thank you to all EarthSky community members who submitted – and are still submitting – photos. Visit EarthSky’s community photo page for more. And submit your photo here.

The 2024 lunar calendars are here! Best Christmas gifts in the universe! Check ’em out here.

Best Geminid meteors images

More Geminids images

More stunning images

More Geminid meteors

And last but not least …

Bottom line: See the best photos of the Geminid meteor shower of 2023 from our talented community of photographers.

The post Geminid meteor shower 2023: Cool photos! first appeared on EarthSky.

An expedition to see emperor penguins

EarthSky friend Eliot Herman took a trip to the Antarctic in late November. After more than 30 hours of flights, he and his wife reached Antarctica, where they got to observe a resident colony of emperor penguins. He shared his fantastic photos with us, and reported from the southern reaches of the world:

We flew to the interior and landed on an ice runway, then to a camp and finally ski-plane to the emperor penguin colony at Atka Bay. With reports of the penguins having reproductive problems, I was concerned about what I would see. The colony we saw had a large population of healthy chubby chicks. A photographer’s dream trip.

Eliot said the travel to get to and from Antarctica was long, but one he has wanted to do for many years. He said:

Seeing the emperors is special, few people do, only a very few of the cruise boats have a chance to go that deep into the Weddell Sea. They often fail, so the number of tourists who see the emperors each year cannot be more than 100 to 200.

The 2024 lunar calendars are here! Best Christmas gifts in the universe! Check ’em out here.

Photos of the expedition

More emperor penguins

The heroes of the trip

See more images of the expedition at Eliot’s Flickr page

Read more on why emperor penguins are endangered

Bottom line: EarthSky friend Eliot Herman took a trip to the Antarctic, where he had the opportunity to visit emperor penguins in their colony. Read his report and enjoy his amazing images.

The post Emperor penguins: A report from the Antarctic first appeared on EarthSky.

Best deep-sky photos from our community

The EarthSky community has many talented astrophotographers who capture stunning images of the deep sky. So enjoy this gallery of some of the best deep-sky photos we have received in October. Do you have some of your own best deep-sky images to share? You can submit them to us here. We love to see them!

The 2024 lunar calendars are here! Best Christmas gifts in the universe! Check ’em out here.

Diffuse nebulae

More deep-sky photos of nebulae

The Orion Nebula

A wide-field view of the constellation Orion

Deep-sky photos of the Ghost of Cassiopeia

The Horsehead Nebula

A galaxy and a star cluster

Bottom line: Enjoy this gallery of the best deep-sky photos of October 2023 from our EarthSky community. And if you have a great photo to share, send it in. We love to see them!

Share your recent Earth or sky photo at EarthSky Community Photos.

The post Deep-sky photos October 2023: Editor’s picks first appeared on EarthSky.

What animal has pointy teeth, is more active at night, and sleeps hanging upside down? You guessed it! A bat.

What are bats?

Many people think of these little animals as dangerous bloodsuckers, like fictional vampires. But there are 1,400 species of bats in the world. Most eat insects, fruits and fish. Only three species of bats feed solely on blood. Not bat, I mean, not bad!

Most bats are small mammals, but there are surprisingly large species too. The largest is the flying fox or Pteropus. It’s a megabat ranging from 4 to 56 ounces (120 to 1,600 grams). Its wingspan is nearly 5 feet (1 1/2 meters).

The smallest is the Kitti’s hog-nosed bat (aka bumblebee bat). This species is about 1.1 to 1.3 inches (27 to 33 mm) in length, and 0.071 ounces (2 grams) in mass, making it the world’s smallest mammal. And speaking of insects, bats are incredible pollinators, too. While insects pollinate flowers during the day, our furry friends pollinate during the night.

If you like bananas, avocados and mangoes, thank a bat. And if you find mosquitoes annoying, well, bats are your best ally. Night insects have the most to fear from bats, as bats are extremely valuable in controlling insect pests. A common bat can eat over 3,000 bugs in just one night. Wow, bon appétit!

The 2024 lunar calendars are here! Best Christmas gifts in the universe! Check ’em out here.

Curious things about bats

Bats have many unique features. For instance, bats are the only mammals that can fly. Yes, we might be mammals ourselves, but we don’t count when traveling by planes or hot air balloons. No cheating!

A bat’s wing resembles a modified human hand. Imagine the skin between your fingers larger, thinner and stretched. This flexible skin membrane that extends between each long finger bone and many movable joints makes bats agile fliers. They are quite fast, too, as they can reach speeds over 100 miles per hour (160 km/h).

And, did you know? We have unique fingertips, and so do they! Well . . . the only difference is that their distinctive prints are in their wings.

Where do they live?

Bats can be found on nearly every part of the planet, except in extreme deserts and polar regions. Before daytime comes, they seek shelter to rest. Bats love caves because they have high ceilings where they can hang. But also, roofs keep them safe from many predators that hunt on the ground.

Some caves can have colonies of up to 20 million bats. But don’t worry. Baby bats won’t get lost among the crowd. Their wings are not the only thing that make them unique. Their voices and scents are also individual! This way, moms can easily find their babies. They have voice recognition, and what is even more impressive, they can navigate by echolocation. This means they can “see” using sounds.

Most bats hibernate, but some of them migrate to warmer areas in search for food.

Vampire bats

Like other mammals, mother bats feed their pups breastmilk, not insects. Most bats give birth to a single pup. Mama bats form nursery colonies in spring in caves, dead trees and rock crevices.

Only three species drink blood. But, no, their teeth are not like straws. What they do is bite another mammal, or sometimes birds, and then lick the blood with their tongues. But don’t worry about their victims, as bats don’t remove enough blood to harm them. Also, this little wound is so subtle that it can sometimes be undetected.

Bats are not only good in the dark sky, but it turns out that they are pretty good on the ground, too. Actually, that’s how vampire bats hunt. They move on the ground and then attack a warm spot to find their victims, with a kind of heat sensor on their noses.

And, did you know? They have anticoagulant in their saliva to help them with their liquid diet. So, they don’t kill their prey, but they can provoke nasty infections and diseases. If you ever find a bat, don’t touch it, as it can carry rabies. Bats are the leading cause of rabies deaths in the U.S.

Bat’s life

It’s said that the smaller the animal, the shorter its lifespan, but bats break that rule of longevity. Most bats live less than 20 years in the wild, but scientists have documented six species that can live more than 30 years. The longest-living bat was judged to be 41 years old; it was a tough old guy from Siberia.

Far from being dirty, bats spend a lot of time grooming themselves. Some even groom each other. They do this because cleaning helps control parasites.

Bats have few natural predators, like owls, hawks and snakes. What has killed millions of bats is the white-nose syndrome, named for a white fungus on the muzzle and wings of bats. This disease affects hibernating bats. Scientists are still working to understand the disease.

At least 12 types of U.S. bats are endangered, and more are threatened. These amazing animals face a multitude of threats including habitat loss and disease.

It’s a pity, as bats have inspired medical marvels. About 80 medicines come from plants that rely on bats for their survival. Also, by studying how bats use echolocation, scientists have developed navigational aids for blind people. Research on bats has also led to advances in vaccines. We could say that, like Batman, bats are the heroes of the night!

Bottom line: Bats might be spooky, but they pollinate flowers, control insect pests, and have inspired scientists around the world to improve human lives in many ways.

Read more lifeform of the week articles

The post Bats, a spooky season icon, are our lifeform of the week first appeared on EarthSky.

Wow. The solar eclipse photos from last Saturday (October 14, 2023) still haven’t stopped coming in. Here are a few more great ones! Thanks to all who contributed to EarthSky Community Photos!

Click here to see our earlier October 14 solar eclipse gallery.
Submit your photo here.

The 2024 lunar calendars are here! Best Christmas gifts in the universe! Check ’em out here.

Solar eclipse photos in composites

The ring of fire

Indirect viewing, and solar binoculars

Solar eclipse photos of stunning landscapes

Family fun

Partial solar eclipse photos

Fun on campus

More ways to see the eclipse

Bottom line: Solar eclipse photos from last Saturday (October 14, 2023) are still coming in. Here are more great ones. Thanks to all who contributed to EarthSky Community Photos!

The post Solar eclipse photos keep coming, and they’re awesome first appeared on EarthSky.

Ants are common insects, but they have some unique capabilities. For example, they have legendary communication skills that allow their colonies to function as superorganisms.

We are newbies in the animal kingdom, but ants have been living since the Cretaceous, arising some 140 to 168 million years ago. Individually, ants are the longest-lived insects. Unlike some bugs that might only live for days or even hours, the queen ant of one particular species – the Pogonomyrmex Owyheei – can live up to 30 years.

There are 20 quadrillion ants on Earth. That’s 2.5 million ants for every human. Ants are members of the family Formicidae. There are more than 12,000 species, and some experts estimate 20,000 exist.

They can be found almost anywhere in the world, with the exception of Antarctica, Iceland, Greenland and some island nations.

Ants’ appearance

Ants range in size from minuscule up to 1 inch (3 cm) long. They are usually black, brown, red or yellow.

Ants don’t have ears, and some of them don’t have eyes! Ants “listen” by feeling vibrations from the ground through their feet, and eyeless ants such as the driver ant species can communicate by using their antennae.

Ants have elbowed antennae and narrow “waists” between the abdomen and thorax. Some ants have wings. Their front wings are longer than their hind wings. The presence of wings indicates an ant’s fertility. Ants with wings are either females that are fertile or males whose job it is to mate with them.

Members of the colony

In a colony, you can find females (workers or queens) and males. While females are diploid (hatched from fertilized eggs, hence possessing two sets of chromosomes, one from the mother and one from her male mate), males are haploid (hatched from unfertilized eggs, hence have just one set of chromosomes, from the mother). Thus, males do not have a father.

Queens are reproductive females that are fully winged in most species.
Workers are non-reproductive (sterile) females that are always wingless. They form the bulk of individuals within a colony.
Males are fully winged (mostly). They are generally present within a colony for only a short time each year and typically live a few weeks, dying very soon after mating.

Typical cycle for a worker ant

Egg: Laid in the ant colony and looked after by other workers.
Larva: Once it emerges from the egg, the larva then begins to develop.
Adult: It can take around 6-10 weeks for an ant to reach the adult stage.

For the queen in any colony, their lifespan may last up to around 15 years, while the worker ants live for roughly seven years. This is, of course, if they can avoid predators and other dangers.

Most of the ants a person sees are female. Male ants, also called “drones,’ do not perform any work in the colony. Their only job is to fertilize the queen ant so she can lay eggs and support the population in the nest.

What are their characteristics?

The ant is one of the world’s strongest creatures in relation to its size. A single ant can carry 50 times its own body weight, and they’ll even work together to move bigger objects as a group!

Ants hold the record for the fastest movement in the animal kingdom. A species of trap jaw ant can close its jaws at 140 mph (125 kph), which it uses to kill its prey or injure predators.

The largest ant nest ever found was more than 3,700 miles (6,000 km) wide. Found in Argentina in 2000, the enormous colony housed 33 ant populations that had merged into one giant supercolony, with millions of nests and billions of workers.

Ants’ behavior and diet

As social insects, ants live in structured nest communities that may be located underground, in ground-level mounds or in trees.

A single ant colony can contain hundreds of thousands of individual ants. Communities are headed by a queen or queens; some species can have as few as two or up to thousands of queens. Queens lay thousands of eggs to ensure the survival of the colony.

Worker ants, the most visible colony members, are females that never reproduce, but instead forage for food, care for the queen’s offspring, work on the nest, and protect the community.

Ants communicate and cooperate by secreting pheromones, or scent chemicals, released through their body to send messages to other ants. They send out warnings when danger’s near, leave trails of pheremones leading to food sources and even use them to attract a mate, like a love potion. How romantic!

They typically eat nectar, seeds, fungus or insects. However, some species have diets that are more unusual. Army ants, with their large mandibles and painful stings, may prey on reptiles, birds or even small mammals.

Ant colonies are so efficient that they can pass useful knowledge between generations. This kind of communal knowledge is essential for defense, so ants can easily differentiate friendly and hostile forces.

An amazing social system

Ants dispose of their dead. They even have undertakers to do this. When an ant dies inside the nest, they carry the body outside to prevent diseases and infections from spreading and affecting the rest of the colony. When an ant dies, its scent changes because the corpse releases something called oleic acid. Other ants detect this new chemical and carry the corpse.

Ants teach their young. As social insects, they have a very advanced system. This way, each group has a specialty, like foraging, cleaning or caretaking of eggs and baby ants.

What’s really interesting is that they’re not born with special skills. They do what we humans do; they learn from those around them. There are teachers that show them how to do a task, and if they are too slow or lack that talent, then they must do another job that doesn’t require special abilities.

How an ant colony begins

Ants can harvest, herd and milk. They actually started farming before we did, 50 million years ago. Before moving out of her birth nest, a young queen must sneak inside the garden she used to live in to take away some seeds and fungal pellets to start her own garden and feed her brood.

So, she takes a blob of fungus in her mouth, taken from the established fungal garden she used to live in, and leaps in the air for a mating flight, gathering enough sperm to keep laying eggs for the rest of her life, which can be as long as 10 years. Then she lands, sheds her wings, finds a burrow in the ground, and starts a new colony.

She spits out her fungal blob, and it begins to grow. The queen lays her eggs in the fungus. The larvae feed on it, and once the first worker ants hatch, they help the queen to tend the garden.

Eco-friendly ants

Ants use herbicides and disinfectant in their fungal gardens. But their substances are far more eco-friendly than human-made ones. The fungal gardens they grow are also home to a virulent type of fungus that kills the fungal crops, preventing them from spreading.

Ants have bacteria at their disposal; they carry them on their cuticles (the hard outer layer they have instead of skin). These bacteria produce an antibiotic that suppresses the growth of the fungal weed. In their nests, they use several substances that inhibit the spread of parasites or weeds.

Leafcutter ants are industrious creatures known for expertly carving up foliage and then carrying it back in pieces to their colony. They use the leaves to farm fungus.

Several species of ants have a special symbiotic relationship with aphids. Aphids feed primarily on the sap from plants and secrete a liquid called honeydew. This secretion is very sugar-rich, and ants crave it. It’s a great food source.

As a result, a system has been hashed out by these insects wherein the ants herd the aphids around to the juiciest parts of plants, protect them from predators, and carry them into their nests at night and for winter. In return, they are allowed to “milk” the aphids, tapping the aphids with their antennae, coaxing them to secrete their honeydew, which is then lapped up by the ant. The little bugs are considered pests by every farmer on Earth, except for their friendly six-legged keepers, the herder ants, which treat the bugs as their dairy cows.

Underground cities

Ants build amazingly complex and stable structures. From the outside, you might only see a hole disappearing into the ground, but beneath the surface, there are many tunnels, branches and chambers that serve as home for the colony’s queen, as nurseries for the young, as farms for fungus cultivated for food, and as trash dumps. They are underground cities, some of them home to millions of individuals, reaching as far as 25 feet (8 meters) underground, often lasting for decades.

This kind of construction would be an impressive undertaking for most creatures, but when performed by animals that don’t get much bigger than your fingernail, it is especially remarkable.

Watch this amazing video of an excavation of an underground ant city.

Unusual ants

Within the many thousands of known ant species, there are many that are unique, resulting in the development of special physical characteristics and interesting behavior.

For example, ants have a variety of biological defenses. Fire ants might be little, but they bite and sting with a venom called solenopsin, which causes a burning sensation, hence the name “fire ant.” They can also survive floods by clumping together to float on the water’s surface.

Other species, like the Pheidole drogon, have evolved to grow spikes or spines from their exoskeletons.

One Amazon species, the Allomerus decemarticulatus, cooperatively builds extensive traps from plant fiber. When an insect steps on one of the trap’s many holes, hundreds of ants inside use the openings to seize it with their jaws.

The bullet ant is said to have the most painful sting in the world. Living in humid jungle areas such as the Amazon, their sting has been compared to being hit by a bullet.

Culture and history

Ants can be used to stitch up wounds. Minor wounds are normally just annoying, with advanced medicine a call away. But imagine you’re in the middle of nowhere and with no first-aid kit or hospital. Then you could use the army ants’ strong pincers. In Maasai tribes, they have the ant bite on both sides of the wound, break off its body and leave behind the head. It can mean the difference between life and death when no other resources are available.

Thank you to the amazing photographers from Pexels, Unsplash and Wikipedia.

Bottom line: Ants are common insects with unique capabilities. They can be found almost anywhere in the world and can harvest, herd and milk. They can also build amazingly complex and stable underground cities.

Read more lifeform of the week articles

The post Ants, little but tough: Lifeform of the week first appeared on EarthSky.

Behold water lilies!

You will find water lilies in parks, gardens and ponds, in places where it stays fairly warm. They can bloom in a range of colors, anytime from late spring through fall.

The showy, fragrant, solitary flowers are borne at or above the water surface on long stalks attached to underwater stems. Each cuplike flower has a spiral arrangement of its many petals. Some flowers open only in the morning, or in the evening, to attract insect pollinators. Their seeds fall and then float away or sink.

Water lilies can grow in a rainbow of colors, including pink, red, orange, yellow, purple, and blue. Sometimes the blossoms change shades as they age. Even the leaf colors vary from deep green to burgundy red.

While water lilies may be most visible on the surface of still freshwater, they are rooted in the mud below, where they overwinter and regrow the following year.

Their floating leaves – which may be cup-shaped, star-shaped, smooth or jagged – are designed to float on the water’s surface. This adaptation lets them maximize their exposure to sunlight, making water lilies efficient at photosynthesis.

Water lilies are known for their rapid rate of growth. Under ideal conditions, they can produce new leaves and flowers within a matter of days, creating a visually striking display in a short period.

Some water lily species, such as the night-blooming water lily, have flowers that open at dusk and close by morning. These nocturnal blooms look mysterious and alluring.

Where to find them

Water lilies are native to the temperate and tropical parts of the world.
They grow in the Americas, Europe, Asia, Africa and Australia.

Water lilies are highly adaptable. They can thrive in various aquatic environments, including ponds, lakes and slow-moving rivers. They have a remarkable ability to grow in both shallow and deep water.

Types of water lilies

There are about 70 species of water lilies. With proper care, water lilies can live for several decades. Some species have been known to survive for over a hundred years.

The world’s largest water lily is the Victoria boliviana, with leaves growing to nearly 10 feet (3 meters) wide in the wild. The largest specimen of the species can be found in La Rinconada Gardens in Bolivia, with leaves of up to 10.5 feet (3.2 meters) wide. The leaf of this giant water lily can support a weight of at least 176 pounds (80 kg). The species wasn’t officially identified until 2022. Before that, it was commonly and mistakenly believed to be Victoria amazonica, one of two previously known species of giant water lily.

The smallest species of water lily is the Nymphaea thermarum. It has pads 0.3 to 0.6 inches (7.6 to 15 mm) across. Botanists believe that this species, also known as thermal lily, is extinct in the wild. Its only natural habitat was a single thermal pool in Mashyuxa, Rwanda, but a change in conditions due to agricultural use is thought to have changed conditions in the pool. So this pool is now uninhabitable for the plant. But horticulturalist Carlos Magdalena of Spain was able to save the lily from extinction. He did this by successfully germinating stored seeds at Kew Gardens, London, U.K., in 2009.

On May 3, 2002, scientists announced the discovery of fossilized remains of a plant in a slab of stone in northeast China. They named them Archaefructus sinensis and said this fossil’s closest living relative may be the water lily. The ancient plant – believed have lived at least 125 million years ago – lived in clear shallow water, with its flowers and seeds extending above the surface.

Water lilies and the environment

Although they’re primarily known for their stunning appearance, water lilies also play an important part in an aquatic ecosystem. Because they rest on the water’s surface, the flowers and pads provide shade, keeping the water cooler and preventing algae that thrive in heat from growing in excess. Water lilies also shelter fish from predatory birds and the heat of the sun. And they are oxygenators, providing essential oxygen for fish and other organisms.

Also, the flowers attract pollinators such as bees and butterflies.

Symbolism

Water lilies mean many things in different areas of the world, but they have special significance in Buddhism and Hinduism. For these religions, the water lily symbolizes resurrection, because these flowers close up at night and reopen in the morning, similar to a spiritual rebirth.

Buddhists also believe that the water lily represents enlightenment because a beautiful bloom emerges from the dark mud.

Water lilies also held great significance in ancient Egyptian and Hindu cultures. The ancient Egyptians associated the blue water lily (Nymphaea caerulea) with the sun god and it was often depicted in art.

Interesting facts

Certain varieties of water lilies emit a pleasant fragrance, adding an enchanting aroma to any garden or pond. The scent varies depending on the species and can range from subtle to strong and intoxicating.

The tubers or roots of some water lily species are edible and have been used in traditional cuisines in various countries.

Some traditional medicinal practices use water lilies for their healing properties. They are believed to have anti-inflammatory and analgesic effects and can be applied topically to treat skin conditions.

Thank you to the amazing photographers from Pexels and Unsplash.

Bottom line: Water lilies are plants known worldwide. They are colorful and beautiful, and they are also important players in the aquatic ecosystem. Learn more about these plants capable of supporting impressive weights.

Read more lifeform of the week articles

The post Water lilies, beautiful and colorful: Lifeform of the week first appeared on EarthSky.

Take a look at this contrail photo, which prompted a long discussion here at EarthSky. Soumyadeep Mukherjee in India told EarthSky he was photographing a sundog in the late afternoon of July 19, 2023, when the sun was low in the west, at an altitude of 12 degrees. Then, he wrote:

I noticed a contrail in my frame (I was imaging at 150mm focal length). I zoomed in (600mm) and noticed the colors on the contrail.

He said he couldn’t see the colors with the eye alone. But they were noticeable with the zoom. So, he captured around 20 images within a span of 30 to 40 seconds, he said, using a high shutter speed (f/9, 1/1600s, ISO 250).

And then he chose seven from which to make the collage you see at top.

But what is it, really?

They are rainbow colors, yes. But this isn’t a rainbow phenomenon. Rainbows take many forms, but, essentially, they are curved bows, seen on the opposite side of the sky from the sun.

And some people do capture photos of true iridescent clouds. We’ve seen some at our community photo page. Iridescent clouds also have rainbow colors. You can read about iridescent clouds here. But … they are clouds.

Soumyadeep’s photo does clearly show a contrail. And, at Les Cowley’s great website Atmospheric Optics, Les has photos and an explanation of iridescent contrails. That’s right, they do exist!

But we weren’t sure that’s what Soumyadeep had captured.

So we dropped a note to Les Cowley, and he graciously replied.

Not iridescent contrails … but beautiful and unusual!

Les wrote:

[You can] think of aircraft contrails as clouds, they have tiny water droplets just like nature’s clouds. These can diffract sunlight to form iridescent colors. More about them on my site here.

But I think the colors in the picture are not aircraft trail iridescence. There is some evidence for strips of thin cloud that are below the contrails. The contrails appear to be lit by a very low or setting sun. The lower cloud droplets [the clouds below the contrails] are diffracting the light of the bright contrails to form the colors.

The reason I support this explanation is that the colors are where the contrails are thick some distance from the aircraft. Look at the image on my site and you will see the colors close to the aircraft, where the trails are thin.

Those regions have droplets of just the right size formed by air passing over the wings and fuselage.

The thick trails are from moisture condensed from the engine exhausts.

An unusual picture!

Thanks, Les. An unusual picture indeed. Thank you again, Soumyadeep!

Bottom line: They look like iridescent contrails. But, are they? We asked the atmospheric phenomena expert Les Cowley, who gave a different opinion.

The post Iridescent contrails? Rainbow contrails? Something else? first appeared on EarthSky.

Happy International Tiger Day! July 29 is the day we celebrate the world’s biggest cats: tigers.

Where do tigers live?

Tigers are the largest cats in the world. They evolved into nine subspecies, six of which still exist: Bengal tiger, Indochinese tiger, Siberian tiger, Malayan tiger, Sumatran tiger and South China tiger. Three of them are extinct: Bali tiger, Javan tiger and Caspian tiger.

As you might have figured out by their names, tigers live in Asia. They migrated from Africa to Asia. They live in different environments, from rainforests to mountains. While they can adapt quite well to many conditions, most species prefer it warm and moist. The lack of prey is a problem, as they eat 50 to 60 large animals per year.

The Bengal tiger is the most numerous. It represents 50% of the worldwide wild population. Tigers can live for about 25 years. However, most die before turning 20 years old.

Their physical appearance

On average, tigers weigh 450 pounds (204 kg). The largest is the Siberian tiger, measuring around 13 feet (four meters) long and weighing up to 661 pounds (300 kg).

They could have a career as sprinters, as they can reach speeds as crazy as 37 mph (60 km/h). They’re not the fastest animals – that’s cheetahs with their top speed of 58 mph (94 km/h) – but it’s still quite impressive. Tigers are fast thanks to their muscular legs, but only for short distances.

Tigers have more muscle mass than lions, which is why they are heavier. So, lions might be the kings of the jungle … but tigers are the bodybuilders of nature. You surely don’t want to mess with them. Even if you want to high five them, you better keep your hands to yourself, because one swipe from a tiger’s front leg is enough to kill a person or animal, or at least break their bones. A tiger’s diet varies depending on where it lives, but some of the large animals it can eat are deer, water buffalos, and wild pigs.

Tiger stripes

Tigers can camouflage themselves behind thick bushes thanks to their stripes. This helps them lie in wait and attack from behind. People living in communities near tigers wear masks behind their heads to trick tigers so there’s no “behind” to sneak up on. But fortunately, tigers don’t usually attack humans. Also, they are quite solitary and like to go for quiet walks.

All tigers have stripes in both their fur and skin. And their stripes are unique, like human fingerprints. The coloration of their fur is caused by the pigments eumelanin (for the black fur) and pheomelanin (responsible for the orange fur). White tigers have a mutated version of gene SLC45A2. This is why they lack the orange color. Another interesting fact is that white tigers are a type of Bengal tigers.

Tigers’ behavior

In general, tigers are nocturnal animals. That means they hunt and protect their territory during the night. One of the reasons they prefer darkness is to avoid conflict with humans. Actually, they have bubbly personalities and are well known for being humble. Male tigers allow females and cubs to eat first … What gentlemen!

Fun facts about tigers

While most cats hate water, tigers have adapted to a life close to water sources. They even have webbed toes and enjoy a nice bath. They are amazing swimmers, thanks to their powerful muscles.

Another fun fact about them is that they can imitate the call of other animals. And did you know that a group of tigers is called an ambush or streak? Also, they can mate with other big cats. This is how tigons and ligers are born.

Tiger cubs are born blind, so they need to follow the scent of their mothers to survive. If they can’t keep up, they die of hunger or cold. Consequently, only half of them survive. Their mothers teach them how to hunt, and they can even kill in the water. As adults, they are capable of swimming for hours and kilometers! And they even eat fish.

Tigers possess antiseptic saliva, so when they lick an area where they have been hurt, they are preventing this area from getting infected. They are pretty good doctors, aren’t they? But even though they are fast, strong and good healers, they face many challenges.

How many tigers are there?

There are less than 4,000 tigers in the wild. Around the year 1900, the tiger population in Asia was around 100,000. But due to deforestation and human development, in the year 2000 the number of tigers was down to 3,800. That means 96% of the population has disappeared.

Beautiful, powerful, fast, strong, unique … That’s why they are so loved! If you care about these magnificent animals, you can help them thrive by collaborating with the many different organizations and programs that try to raise awareness of their poor situation and help them live their best lives. Two great organization are the Wildlife Conservation Society and the World Wildlife Fund.

Thank you to the amazing photographers from Pexels and Unsplash.

Bottom line: Tigers are huge, fierce cats that are unique and beautiful. We tell you some curious facts about them here.

Read more lifeform of the week articles

The post Tigers are the biggest cats: Lifeform of the week first appeared on EarthSky.

Sea turtles are like marine dinosaurs

Sea turtles have existed since the time of the dinosaurs. The earliest marine turtle lived about 120 million years ago. The Desmatochelys padillai was 6 feet (183 cm) long and looked like modern turtles, as it also had a carapace (hard shell) and paddle-like limbs.

Today, there are seven species of sea turtles. From smallest to biggest, they are: Kemp’s ridley, olive ridley, hawksbill, flatback, green, loggerhead and leatherback. The smallest species can reach 2.3 feet (70 cm) long and weight 88 pounds (40 kg), while the leatherback can grow to 6 feet (180 cm) and weigh up to 1,100 pounds (500 kg). It’s larger than the fossils found of its prehistoric ancestor, the padillai.

The largest marine turtle known was a leatherback turtle that washed up on a beach in Wales in 1988. It measured 8 feet (2.5 m) and weighed 1,980 pounds (900 kg)!

Anatomy and feeding habits

Sea turtles don’t have teeth. They have beaks, which are made out of keratin, the same thing our nails are made out of. Turtle shells consist of over 50 bones fused together. So, this literally means they wear their bones on the outside. Also, their bones are light and spongy, which helps them float.

Marine turtles live in most of the world’s oceans, apart from cold polar seas. They tend to spend their lives in relatively shallow continental shelf waters. They might not be voracious killers like sharks, but some turtle species are very important predators that help to keep ocean food chains healthy.

For example, hawksbill turtles eat lots of sea sponges, which would otherwise out-compete reef-building corals. So, the turtles help to protect the coral reefs, which are crucial for the survival of many other creatures.

The leatherback turtle largely eats jellyfish, which helps stop jellyfish from depleting fish stocks. And that benefits other animals in the food chain, as well as people.

Sea turtles are natural navigators

Sea turtles can migrate over incredibly long distances. A female leatherback holds the record. She swam nearly 13,000 miles (21,000 km) over 647 days from Indonesia to the West Coast of America.

Sea turtles use Earth’s magnetic fields to navigate. If they were X-Men, they would have geomagnetic abilities. They have an internal biological GPS. They have particles of magnetite (a magnetic mineral) in their brains. The magnetite plays a role in orienting sea turtles to Earth’s magnetic poles. So, they have this map “printed” in their brains since the moment they are born.

Eggs and nests

The sex of turtles is not determined by sex chromosomes, as in most vertebrates. It’s the temperature of the nest that determines the sex of the hatchlings (baby sea turtles). If the temperature is warm, around 88 degrees Fahrenheit (31 Celsius), most of the hatchlings will be female. So, when temperatures are lower, around 82 degrees Fahrenheit (28 C), then most of the hatchlings will be male.

Once mature, male turtles never leave the sea. But females come ashore to lay eggs, typically on the same sandy beach where they themselves hatched, thanks to their biological map.

The females dig a hole in the sand, then lay their eggs. They can lay more than 150 eggs at a time! A clutch is the name for a group of unhatched eggs. After laying eggs, the mother returns to the sea, leaving the little creatures to their fate.

Less than 1% of the hatchlings will survive to reach adulthood. Predators such as crabs and birds often kill the hatchlings as they make their way from the nest to the sea. And when they reach the shallows, fish eat many more of the newborn turtles. Life as a marine turtle is tough from day one!

Threatened with extinction

These amazing creatures have been navigating our oceans for millions of years. They are brilliant navigators, swimming hundreds or thousands of miles, but they face lots of threats along the way. Even under “natural” conditions, relatively few young marine turtles survive their first year of life.

They need our help to survive because they’ve been affected by human activities, such as fisheries, illegal wildlife trade and climate change.

All seven sea turtles species are threatened with extinction. Their populations have dramatically declined in the past two centuries. They get caught in fishing nets, and people use them to create turtle products. But one of the worst threats is plastic. Plastic pollutes their habitats. Then they eat it, it poisons them and then they die. Or they get stuck among plastic trash. Around 13 million tons of plastic end up in the water every year.

And if temperatures keep rising due to climate change, there will be more females than males, skewing the sex ratios.

Light pollution and sea turtles

According to the International Dark Sky Association:

Of all the animals on our planet, perhaps none are under more threat from light pollution than sea turtles. Sea turtles live in the ocean, yet they hatch at night on sandy beaches. Hatchling sea turtles have one immediate goal to ensure their future survival: find the ocean. They have evolved to locate the sea by seeing the brighter horizon over the ocean, and moving away from landward silhouettes. On a natural beach the newly hatched sea turtles find the open horizon and make for the water.

Adult female sea turtles have a hard time finding an appropriately dark beach for laying their eggs, and the lights of our cities confuse their hatchlings. Instead of reaching the safety of the ocean, the newborn sea turtles often head for illuminated roads, civilization, danger and death. In Florida alone, millions of hatchling sea turtles die this way every year.

So if you live near the beach, turn your lights out for sea turtles!

What else you can do

There’s even more you can do to help save turtles.

Many organizations keep beaches clean. Also, they use signs and tape around the nests, to keep people from disturbing the turtles. Plus, they look out for the nests when the mothers leave the beach. Thanks to these mediations, they can help stop the decline of sea turtles.

Stop plastic at its source, and take responsibility for your plastics. Be part of the solution. Let the native marine life have free and healthy lives in the oceans they have navigated for millions of years before us.

Thank you to the amazing photographers from Pexels, Unsplash and Wikimedia.

Bottom line: All you need to know about sea turtles: as old as the dinosaurs, incredible navigators and natural survivors. But they need you. Learn what you can do to help.

Adopt a turtle

How WWF protects sea turtle species across the Pacific

How you can reduce plastic waste

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The post Sea turtles are as old as dinosaurs: Lifeform of the week first appeared on EarthSky.