The Tiny “Toad” of Many Crowns

This exercise is a part of Educator Guide: Endangered Migratory Species and A Tiny Toad / View Guide
A tiny brown frog sits just off center on a Brazilian real coin.
The Brazilian flea toad has nabbed the title of world’s smallest known amphibian and smallest known vertebrate. At just 7 millimeters long on average, the frogs are a fraction the size of a 27-millimeter-wide $1 Brazilian real coin.W.H. Bolaños, I.R. Dias and M. Solé/Zoologica Scripta 2024

Directions for teachers:

To engage students before reading the article, have them answer the “Before Reading” questions as a warmup in class. Then, instruct students to read the online Science News article: “The Brazilian flea toad may be the world’s smallest vertebrate.” Afterward, have them answer the “During Reading” questions.

As an optional extension, instruct students to answer the “After Reading” questions as a class discussion or as homework.

This article appears in the March 23, 2024, issue of Science News. Science News Explores offers another version of the same article written at a middle-school reading level. Post this set of questions without answers for your students, using this link.

Directions for students:

Read the online Science News article: “The Brazilian flea toad may be the world’s smallest vertebrate.” Then answer the following questions as directed by your teacher.

Before Reading

1. You’ll need a pen/pencil, a ruler, a blank piece of paper, and a coin (any variety). Trace an outline of your coin on your paper. Measure the diameter and write down your measurement. Now imagine an object that is 7 millimeters (0.27 inch) in diameter sitting atop your coin. Would this object be larger or smaller than the coin? Draw a star on your coin outline approximately 7 millimeters (0.27 inch) in diameter to represent this object.

Answers will vary. But measurements should be accurate, and the coin will probably be bigger than an object that is 7 millimeters (0.27 inch long).

2. Imagine the object in Question 1 is a 7-millimeter-long (0.27 inch) animal. Is an animal this size likelier to be a vertebrate (an animal with a backbone) or an invertebrate (an animal without a backbone)? Explain your answer.

Answers will vary. Many students will likely predict the animal to be an invertebrate because vertebrates are usually bigger than the star they’ve drawn on paper.

During Reading

1. Read the first sentence of this story, then write down what you think this story will discuss. Why did the author open the story with that line?

This story will discuss a very small species of frog. The author uses a metaphor to hook the reader, saying that the frog is too tiny to wear “crowns” on its head for being the smallest known amphibian and vertebrate.

2. List the flea toad’s two “titles.”

The flea is the smallest known amphibian and the smallest known vertebrate.

3. How does the flea toad’s size compare to the previous record holder?

The flea toad is about half a millimeter shorter than the previous record holder.

4. In which country was the flea toad discovered?

The flea toad was discovered in Brazil.

5. What is the scientific name for the previous record holder?

The scientific name for the previous record holder is Paedophryne amanuensis.

6. Describe two anatomical differences between the frogs in this article and more typical frogs.

The Brazilian flea frog has two toes rather than the typical five. Some species of tiny frogs also differ from regular frogs in the shapes of their inner ears.

After Reading

1. Why is the name “flea toad” misleading? How might the animal’s name be changed to more accurately describe this species?

The name “flea toad” is misleading because the animal is neither a flea nor a toad. “Flea frog” or “flea amphibian” are two examples of an alternative names, but answers will vary.

2. What are some physical features of this animal that might hint at the misleading nature of its name? Feel free to do a quick internet search.

Most students will likely refer to the smooth/slimy/moist texture of a frog’s skin vs. the drier, bumpier toad skin as evidence of the flea toad’s misleading name.