Is It True That T. Rex Could Only See Things That Were Moving?

Freer Law/iStock via Getty Images
Freer Law/iStock via Getty Images

I rewatched Jurassic Park a few weeks ago and, from the story to the special effects, it still holds up. But I’ve been nagged by one thing that’s stuck with me from the first time I saw the movie—a thing that has been ingrained in our collective knowledge and perception of dinosaurs: protagonist Alan Grant's assertion about what the Tyrannosaurus rex can and can’t see.

In the scene where the T. rex gets loose and attacks a group of human characters, Grant says to Lex, “Don’t move. It can’t see us if we don’t move.” Sure enough, the dinosaur gets up in their faces without noticing them right after he says that. For what it's worth, Michael Crichton does explain in the Jurassic Park novel that the amphibian DNA used to help bring the dinosaurs to life hobbled their visual cortices. Director Steven Spielberg and the movie's screenwriters dropped the ball big time here, importing the dinosaurs’ vision problems but not the explanation for them. Instead, in the movie, Grant comes off like he’s stating an accepted dino fact.

Sci-Fi versus Reality

He’s not. In the last few years, real-world paleontologists have proven Dr. Grant very wrong. In 2006, Kent Stevens from the University of Oregon did an experiment inspired by that very scene to figure out what sort of binocular range (the field of view both eyes can see simultaneously) T. rex might have had. The wider that range, the better an animal’s depth perception and capacity to distinguish objects that are motionless or camouflaged.

Stevens built a scale model of the T. rex’s head and popped in some taxidermic eyes based on the eyes of three animals pretty closely related to T. rex—alligators, ostriches, and eagles—and adapted for situations that a dinosaur would have likely encountered. As he explains on his website, he used a technique called “inverse perimetry” to estimate “whether a given probe would be visible, based on whether there is a clear, unobstructed view of the pupil along a line of sight,” and mapped the model’s field of view.

Stevens' model study suggests that T. rex had a binocular range of around 55°, better than that of modern-day hawks and eagles. And it would have only gotten better. Paleontologists know from the fossil record that, over millennia, T. rex’s eyes got larger and its snout got lower and narrower, giving it even clearer sight lines than Stevens’ model.

For more on dino-vision, see Stevens' web page and the study. For more on other JP mistakes that make dino geeks fume, see this Wikipedia list.

Amazon’s Big Fall Sale Features Deals on Electronics, Kitchen Appliances, and Home Décor

Dash/Keurig
Dash/Keurig

If you're looking for deals on items like Keurigs, BISSELL vacuums, and essential oil diffusers, it's usually pretty slim pickings until the holiday sales roll around. Thankfully, Amazon is starting these deals a little earlier with their Big Fall Sale, where customers can get up to 20 percent off everything from home decor to WFH essentials and kitchen gadgets. Now you won’t have to wait until Black Friday for the deal you need. Make sure to see all the deals that the sale has to offer here and check out our favorites below.

Electronics

Dash/Amazon

- BISSELL Lightweight Upright Vacuum Cleaner $170 (save $60)

- Dash Deluxe Air Fryer $80 (save $20)

- Dash Rapid 6-Egg Cooker $17 (save $3)

- Keurig K-Café Single Coffee Maker $169 (save $30)

- COMFEE Toaster Oven $29 (save $9)

- AmazonBasics 1500W Oscillating Ceramic Heater $31 (save $4)

Home office Essentials

HP/Amazon

- HP Neverstop Laser Printer $250 (save $30)

- HP ScanJet Pro 2500 f1 Flatbed OCR Scanner $274 (save $25)

- HP Printer Paper (500 Sheets) $5 (save $2)

- Mead Composition Books Pack of 5 Ruled Notebooks $11 (save $2)

- Swingline Desktop Hole Punch $7 (save $17)

- Officemate OIC Achieva Side Load Letter Tray $15 (save $7)

- PILOT G2 Premium Rolling Ball Gel Pens 12-Pack $10 (save $3)

Toys and games

Selieve/Amazon

- Selieve Toys Old Children's Walkie Talkies $17 (save $7)

- Yard Games Giant Tumbling Timbers $59 (save $21)

- Duckura Jump Rocket Launchers $11 (save $17)

- EXERCISE N PLAY Automatic Launcher Baseball Bat $14 (save $29)

- Holy Stone HS165 GPS Drones with 2K HD Camera $95 (save $40)

Home Improvement

DEWALT/Amazon

- DEWALT 20V MAX LED Hand Held Work Light $54 (save $65)

- Duck EZ Packing Tape with Dispenser, 6 Rolls $11 (save $6)

- Bissell MultiClean Wet/Dry Garage Auto Vacuum $111 (save $39)

- Full Circle Sinksational Sink Strainer with Stopper $5 (save $2)

Home Décor

NECA/Amazon

- A Christmas Story 20-Inch Leg Lamp Prop Replica by NECA $41 save $5

- SYLVANIA 100 LED Warm White Mini Lights $8 (save 2)

- Yankee Candle Large Jar Candle Vanilla Cupcake $17 (save $12)

- Malden 8-Opening Matted Collage Picture Frame $20 (save $8)

- Lush Decor Blue and Gray Flower Curtains Pair $57 (save $55)

- LEVOIT Essential Oil Diffuser $25 (save $5)

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Why Do Dogs Like to Bury Things?

Dogs like to dig.
Dogs like to dig.
Nickos/iStock via Getty Images

If you’ve ever found your dog’s favorite toy nestled between pillows or under a pile of loose dirt in the backyard, then you’ve probably come to understand that dogs like to bury things. Like many of their behaviors, digging is an instinct. But where does that impulse come from?

Cesar's Way explains that before dogs were domesticated and enjoyed bags of processed dog food set out in a bowl by their helpful human friends, they were responsible for feeding themselves. If they caught a meal, it was important to keep other dogs from running off with it. To help protect their food supply, it was necessary to bury it. Obscuring it under dirt helped keep other dogs off the scent.

This behavior persists even when a dog knows some kibble is on the menu. It may also manifest itself when a dog has more on its plate than it can enjoy at any one time. The ground is a good place to keep something for later.

But food isn’t the only reason a dog will start digging. If they’ve nabbed something of yours, like a television remote, they may be expressing a desire to play.

Some dog breeds are more prone to digging than others. Terriers, dachshunds, beagles, basset hounds, and miniature schnauzers go burrowing more often than others, though pretty much any dog will exhibit the behavior at times. While there’s nothing inherently harmful about it, you should always be sure a dog in your backyard isn’t being exposed to any lawn care products or other chemicals that could prove harmful. You should also probably keep your remote in a safe place, before the dog decides to relocate it for you.

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