Why parent no-arg constructor is called?

Question

public class Animal {
    public Animal() { System.out.print("Animal"); }
    public Animal(int age) { System.out.print("AnimalAge"); }
    private boolean hasHorns() { return false; }
    
    public static void main(String[] args) {
        Animal animal = new Elk(5);
        System.out.println("," + animal.hasHorns());
    }
}

class Elk extends Animal {
    public Elk(int age) { 
        System.out.print("Elk");
    }
    
    public boolean hasHorns() { return true; }
}

compiles and I dont understand the output

"Since there is no explicit call to the parent constructor, the default no-argument super() is inserted as the first line of the constructor"