If You Give a Shark a Cookie…

July 22, 2026

AI Summary

5 min read

In June of 2026, researchers announced a new species of shark discovered near Papua New Guinea that uses its fins to walk along coral reefs. That discovery is just one of many recent findings reshaping what scientists know about these ancient predators, and this episode of Curiosity Weekly dives into the frontier of shark research—from how ocean acidification may corrode their teeth to whether great whites can learn, and even whether all sharks are really sharks.

What Ocean Acidification Does to Shark Teeth

A study published in August 2025 in Frontiers in Marine Science tested what happens when shark teeth are exposed to the more acidic ocean conditions projected for the year 2300. Scientists at Sea Life Aquarium in Germany collected over 600 discarded teeth from blacktip reef sharks—animals that must swim with their mouths constantly open to breathe, meaning their teeth are perpetually bathed in seawater. They selected 52 teeth in good condition and split them between two tanks: one at the ocean’s current pH of about 8.1, the other at 7.3, representing nearly a tenfold increase in acidity.

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What you'll learn

1 (00:00) **Sponsor Pre-Roll & Episode Kick-Off** - A series of sponsor ads for Capital One, Walmart Business, and Farmers Insurance, followed by the show's Shark Week introduction.
2 (03:26) **Ocean Acidification & Shark Teeth** - A study predicts that by 2300, acidic oceans could corrode shark teeth, similar to an egg in soda.
3 (06:59) **Mid-Roll Sponsor Break** - Ads for Creative Planning, 877-CASH-NOW, and Grainger.
4 (08:20) **Interview: Dr. Tristan Gutridge on Shark Social Lives** - The host introduces Dr. Tristan Gutridge, a shark behavior expert, to discuss the social complexity of sharks.
5 (11:41) **Training Great Whites: Scaling Up Cognition Tests** - Tristan discusses his Shark Week show "How to Train a Shark," testing whether great whites can learn.
6 (13:33) **What Sharks Learn: Hunting, Navigation & Social Cues** - Sharks learn from experience and each other, as they are born without parental guidance.
7 (15:35) **Choosing a Focus: From Lemon Sharks to Hammerheads** - Tristan explains his shift from studying behavior to conservation, focusing on endangered hammerheads.

+ Full timestamped outline available in the app

Show Notes

It’s that time of year again… #SharkWeek starts July 26 on Discovery and HBO Max. To celebrate, Dr. Samantha Yammine is joined by renowned shark behavior expert and Shark Week star, Dr. Tristan Guttridge. The two talk all things sharks; from their social dynamics to their genetics to their migration patterns and beyond.

Before that, Sam looks at a study that explores how ocean acidification corrodes shark teeth. Later, new research is causing conversation about whether or not we’re classifying sharks the right way and reveals how some of their key traits evolved over millions of years.

Link to Show Notes HERE

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