Why am I getting compile error in JavaScript when extending a class with a default constructor?

I’m trying to create a subclass in JavaScript and am encountering an error related to the use of this in the subclass constructor. Here’s the code I’m working with:

class Mammals {
  // No constructor defined explicitly
}

class Humans extends Mammals {
  constructor(name) {
    this.name = name;
  }
}

const jimmy = new Humans("Jimmy");
console.log(jimmy.name);

I understand that if a base class has a default no-argument constructor, JavaScript should allow the subclass constructor to run without explicitly calling super(). I thought that since Mammals has a default constructor (as it’s not explicitly defined), the Humans constructor should not need to call super().

However, I am still encountering the error message:

Must call super constructor in derived class before accessing ‘this’
or returning from derived constructor

Can someone explain why

Thank you for your help!