How are alligators and crocodiles different?

Asia's Tech News Daily

How are alligators and crocodiles different?
© Provided by Live Science null

All alligators and crocodiles belong to a taxonomic order called Crocodylia. Crocodylia is then split up into three major families; Alligatoridae (alligators), Crocodylidea (crocodile) and Gavialidae (gharial), according to the journal Pathology of Wildlife and Zoo Animals

These Crocodylia share a common evolutionary ancestor; however, around 80 million years ago – during the Late Cretaceous period – Alligatoridae and Crocodylidae diverged and continued along their own evolutionary journey, according to the New York Times. Over millions of years of evolution, both crocodiles and alligators have remained relatively similar in their appearance, but there are some surprising differences that are easy to spot. 

Related: Mystery of extinct horned crocodile solved after 150 years

Do alligators and crocodiles look different?

At first glance, crocodiles and alligators look quite similar; however on closer inspection, the two have very different snouts. There is one quick-fire way to distinguish a crocodile from an alligator: Look at their jawline. Alligators have an overbite, and so the teeth on the bottom jaw fit into sockets in the top jawline and are concealed. The teeth on the bottom row of a crocodile’s jaw, on the other hand, sit on the outside of the mouth and slot into grooves along the top jaw, according to Biology and Evolution of Crocodylians. The shape of their heads is also a key identifier. Alligators have a U-spaced rounded snout that is  wide and short, whereas crocodiles have a longer pointed, V-shaped snout. There are some exceptions to the rule, such as the mugger crocodile (Crocodylus palustris), which has a rounded snout reminiscent of an alligator, according to San Diego Zoo Wildlife Alliance

Both of these reptiles have tiny black specks called integumentary sense organs (ISOs) on their heads. These sensory organs allow the predators to detect pressure changes in the water caused by potential prey. ISOs can be found solely on the head and around the mouth of alligators; crocodiles have ISOs on almost every scale on their body, according to the Journal of Experimental Biology.

Differences between the two reptiles are also much more than skin deep. In a study published in 2018 in the journal Royal Society Open Science, researchers found that, compared with crocodiles, the forelimbs of alligators have a shorter humerus bone and hindlimbs have shorter femurs.

Where do crocodiles and alligators live?

One major difference between alligators and crocodiles is where they live. Crocodiles have lingual salt glands – on their tongues – which allow them to expel excess salt from their bodies, according to a study published in the Journal of Comparative Physiology. This ability allows them to live in salty marine environments, such as Australia’s saltwater crocodiles (Crocodylus porosus) – which reside throughout mangroves, swamps and deltas. Although alligators have the same salt gland, that gland is not very effective and limits the alligator’s tolerance for salt water. Therefore, alligators stick to freshwater habitats, such as lakes and marshes. 

This difference in salt tolerances could also explain differences in their global distribution. Crocodile species can be found across the Americas, Africa, Asia and Australia, whereas alligators are predominantly found in North and South America, according to National Geographic

Related: Alligators can regrow their tails, surprising scientists

Additional resources

  • For more information about the evolution of crocodiles and alligators check out: The Rise of Reptiles: 320 Million Years of Evolution
  • Herpetology: An Introductory Biology of Amphibians and Reptiles
  • Discover the population status for crocodiles and alligators at the International Union for Conservation of Nature (IUCN) Red List
Internet Explorer Channel Network
Asia's Tech News Daily
News Related

OTHER NEWS

‘The Sopranos' Actress Lorraine Bracco Voices Upset With Dr. Melfi's Exit: “That Was Rough”

On a November 21 episode of the podcast Talking Sopranos, longtime Sopranos cast member Lorraine Bracco addressed her discontent with how her character, Dr. Jennifer Melfi, exited the iconic HBO ... Read more »

Kate Spade's Black Friday Deals Are So Good, We Had to Do a Double Take

Kate Spade Sale Courtesy When you open the Kate Spade website today, you'll be greeted with “OMG!” displayed across the top. And OMG is right — almost everything sitewide is ... Read more »

A Bottle of This Kate Middleton-Approved Anti-Aging Face Oil Sells Every 20 Seconds — and Today It's on Sale

Kate Middleton Chris Jackson/Getty Images Kate Middleton Come Black Friday, popular products disappear faster than a new toy among my three cats — and that's saying something. Yet the adrenaline ... Read more »

These Oprah-Approved Pants Are My Best-Kept Fashion Secret — and They're on Major Sale

Spanx Review Sale Courtesy of Getty Images In my perfect world, I could wear sweatpants, hoodies, and sneakers, but look like I'm wearing Chanel, Gucci, and Christian Louboutin. But as ... Read more »

Kourtney Kardashian Hits the Slopes with Her Kids for Some Thanksgiving Skiing: 'I Love the Snow'

Kourtney Kardashian Kourtney Kardashian/Instagram Kourtney Kardashian celebrated Thanksgiving on the slopes. The Keeping Up with the Kardashians alum, 42, took her three kids skiing over the holiday, as she and ... Read more »

Mum's 'life-changing' 50kg weightloss transformation

When Jala Allouche looks back at photos showing just how far she has come in her transformation, she’s filled with pride and happiness. The mother-of-two said she never dreamt of ... Read more »

‘Wellness warriors': how Victoria's vaccine mandate sparked divisions in progressive Brunswick

Photograph: Benoit Balanca/Getty Images Explanations for why Brunswick’s second-dose rate is 10% or more behind the state average vary – from the younger demographic to the alternative health crowd Victorian ... Read more »

Amazon Shoppers Are Basing Their Entire Winter Wardrobe Around This Skirt and Sweater Set

Daily Ritual Women’s Relaxed-Fit Cozy Boucle Mockneck Sweater Courtesy The only thing we love more than a Black Friday deal is a Black Friday bundle deal. Eagle-eyed sale shoppers know ... Read more »

Westside Story-Composer Stephen Sondheim (91)

Broadwaycomponist Stephen Sondheim is op 91-jarige leeftijd overleden, meldt New York Times..Sondheim enthusiastically rebuked the Van de Musical Westside story, Maar schreef ook onder meer Gypsy en Sweeney Todd.. Hij ... Read more »

Model who married herself 90 days ago is getting divorced

Ninety days ago a Brazilian model married herself; now she is ending the marriage as she has found a new love. In front of a Sao Paulo Catholic church, Cris ... Read more »

TikTok video shows disgusting find in McDonald's drink machine: worms

A disgusting TikTok video by user McOldKentRoad has gone viral as it exposed the filthy condition of a drinks machine at a McDonald’s restaurant. Customers were disgusted after the video ... Read more »

Daniela Elser: The moment Harry and Meghan sabotaged their relationship with the press

OPINION: When Prince Charles announced to the world he had finally found a Sloaney gal willing to take on the mantle of Queen on February 24, 1981, the interview that ... Read more »

Stephen Sondheim, Legendary Broadway Songwriter, Dead at 91

© Douglas Elbinger/Getty Images Stephen Sondheim, the Broadway legend behind shows like Into the Woods, Sweeney Todd, Company and more, has died at 91. Sondheim’s lawyer and friend, F. Richard ... Read more »

Target's Black Friday Toy Sale Will Help You Save Up To 50% Off Everything On Your Kid's Wish List

© Pexels We made it — Thanksgiving came and went — and now it’s Black Friday and time for shopping. And if you’re a parent, that means finding unbelievable deals ... Read more »

Will we ever cure the common cold? We ask the expert

Famously, there is no cure for the common cold. But with the success of the Covid vaccine, could it finally be in grabbing – or, rather, jabbing – distance? I ... Read more »

La marca de café trumpista que ha convertido el Tesla Model X en un coche armado con ametralladoras

© YouTube Todo lo que necesitas saber sobre el café (y el té), sin tener que jugar con ametralladoras. ¡Despierta! Aquí tienes los mejores cafés y cafeterías de España Los ... Read more »

Boots' Black Friday 2021 bestsellers to shop now

Here are all the Boots Black Friday deals to make the most of. (Getty Images) Yahoo Life's editors are committed to independently selecting wonderful products at great prices for you. ... Read more »

John Lewis shares best-selling Black Friday deals as huge sale continues

These are the John Lewis deals to snap up ASAP. (Getty Images) Yahoo Life’s editors are committed to independently selecting wonderful products at great prices for you. We may receive ... Read more »

Amazon Canada Black Friday deal: Save up to 54% on Keurig coffee makers

Looking for more Black Friday deals, gift guides and holiday tips? Sign up for Yahoo Lifestyle Canada’s newsletter! Black Friday deal: Save up to 54 per cent on Keurig machines ... Read more »

Candace Cameron Bure says eating disorder struggle 'never goes away'

Are the Kids Alright? is Yahoo Entertainment's video interview series exploring the impact of show business on the development and well-being of former child entertainers, from triumphs to traumas. Candace ... Read more »

Kanye West Reveals What 'Wife' Kim Kardashian Really Thought Of His MAGA Hat

Kim Kardashian West was less than happy with Kanye West’s wearing of a “Make America Great Again” cap during the rapper’s ill-fated 2020 run for president, according to the hip-hop ... Read more »

This Amal Clooney-Approved Lipstick Makes Your Lips Look Fuller, and It's on Sale Right Now

Amal Clooney Pillow Talk Makeup Courtesy of Getty Images Some lipsticks are just so good, they become instantly famous. And given the sheer number of pout products out there, that's ... Read more »

Amazon Launched Huge Deals on Clothing, Shoes, and Accessories — Here's What to Buy

Best Black Friday Amazon Fashion Deals Courtesy/InStyle When you think of Amazon's Black Friday sale, you probably associate it with deals on big-ticket items, like tech and home goods. While ... Read more »

How 'Queen of Christmas' Elizabeth Chan swapped a marketing job for holiday pop stardom

“This dream of mine to write Christmas music was something that I literally had in my spirit and in my heart, since I was a child,” Elizabeth Chan, a songwriter ... Read more »

Yes So I Said Yes review – prepare to be appalled

Photograph: Tristram Kenton/The Guardian With much current fiction seeking ticks for sensitivity and positive representation, the work of David Ireland is a spectacular defence of free speech and the right ... Read more »

I'm an Amazon Shopping Editor, and These Are the 10 Things Worth Buying on Black Friday

amazon black friday deals Amazon If you never know what to get during Black Friday, I understand. I used to be the same way before I knew where to look ... Read more »

The Best Wayfair Black Friday Deals Just Dropped

Photo credit: wayfair “Hearst Magazines and Yahoo may earn commission or revenue on some items through the links below.” Black Friday is the day to save big on home and ... Read more »

Skincare, Makeup, and Hair Care Start at Only $5 During Amazon's Black Friday Sale

The 15 Best Black Friday Skin Care, Makeup, and Hair Care Deals on Amazon, Starting at $6 Courtesy/InStyle If you've ever spent time shopping for beauty products, you know that ... Read more »

TV host Carolyn Taylor's tears of joy: 'All my dreams have come true'

It was the dream job – a new international travel series that would see Carolyn Keep (nee Taylor) jetting around the world, being paid to explore exotic and luxurious destinations. ... Read more »

10 really good Black Friday UK deals (according to Yahoo's shopping team)

These are the deals we don’t want you to miss. (Getty Images) Yahoo Life's editors are committed to independently selecting wonderful products at great prices for you. We may receive ... Read more »

Met Mahler en een gil de avondlockdown in

Klassiek 2x Marler • Swedish Radio Symphony Orchestra olv Daniel Harding mmv Johanna Wallos (soprano), Chr. Gerhaha (baritone). Marler 4+ De Naven Wonderhorn (24/11) • Budapest Fest. Orkest / I. ... Read more »

What Is Super-Fertility? It's Not As Straightforward As It Sounds

If you’re trying to get pregnant, or even planning to try to get pregnant, you might make the assumption that being ‘super-fertile’ is a good thing. It suggests that having ... Read more »

Do I need to leave my partner for the sake of my fragile son?

Photograph: Alexander Spatari/Getty Images I am 62 years old and semi-retired. I’ve worked hard all my life. In my 30s I had a son; it was just the two of ... Read more »

Kate Spade, Net-A-Porter, Hugo Boss and more designer brands slash prices for Black Friday 2021

Kate Spade is one of many designer labels offering customers big discounts this Black Friday. (Getty Images) Yahoo Life's editors are committed to independently selecting wonderful products at great prices ... Read more »

Amazon Canada's Black Friday sale is your chance to snag this Philips Sonicare electric toothbrush for $58

Looking for more Black Friday deals, gift guides and holiday tips? Sign up for Yahoo Lifestyle Canada’s newsletter! Save 42% on the Philips Sonicare ProtectiveClean Rechargeable Toothbrush. Image via Philips. ... Read more »

Amazon's Secret Outlet Has Designer Brands for Hundreds of Dollars Off During Black Friday

Amazon Black Friday Designer Outlet Deals Getty Images The rumors are true: You can get designer brands for way less on Amazon during Black Friday. The brand's under-the-radar outlet section ... Read more »

How to teach kids to give back — plus easy ways they can help others

How to teach your kids to give back and help others this holiday season and beyond. (Photo: Getty Images) Kids often get a slew of presents over the holidays, which ... Read more »

Ilhan Omar: Boebert is a ‘buffoon' and ‘bigot' for ‘made up' anti-Muslim story

Photograph: Nikolas Liepins/REX/Shutterstock The Minnesota Democrat Ilhan Omar called the Colorado Republican Lauren Boebert a buffoon, a bigot and a liar, for claiming to have joked about terrorism when sharing ... Read more »

Wildly Popular Sex Toys Are Up to 60% Off During Black Friday, so Come Quickly

Best-Selling Sex Toys Black Friday Courtesy instyle – $30 Available at Amazon instyle – $30 Available at Ella Paradis instyle – $28 Available at Lovehoney instyle – $120 Available at ... Read more »

This hardly ever happens, but Apple AirPods are on sale for Black Friday at Amazon

Looking for more Black Friday deals, gift guides and holiday tips? Sign up for Yahoo Lifestyle Canada’s newsletter! Apple AirPods are on sale on Amazon Canada. Yahoo Lifestyle Canada is ... Read more »
On free-english-test.com you will find lots of free English exam practice materials to help you improve your English skills: grammar, listening, reading, writing, ielts, toeic