diff --git a/animals/animal.cpp b/animals/animal.cpp
index 6745215..c6e4f47 100644
--- a/animals/animal.cpp
+++ b/animals/animal.cpp
@@ -1,7 +1,27 @@
 #include "animal.h"
+#include "mammal.h"
+#include "bird.h"
 
-using namespace std;
+void printBirdInfo() {
+	Eagle sharpSightedEagle(12, 1.2, 0.9);
+
+	Parrot niceGreenParrot(5570463, 0.1, 0.3);
+
+	std::cout << sharpSightedEagle << std::endl << niceGreenParrot << std::endl;
+}
+
+void printMammalInfo() {
+	Cat littleKitten(0.05, 60, 0.5);
+	
+	Dog bigScaryDog(Chauchau, 50, 10);
+
+	std::cout << littleKitten << std::endl << bigScaryDog;
+}
 
 int main() {
+
+	printBirdInfo();
+	printMammalInfo();
+
 	return 0;
 }
\ No newline at end of file
diff --git a/animals/animal.h b/animals/animal.h
index 83a1944..2be806f 100644
--- a/animals/animal.h
+++ b/animals/animal.h
@@ -3,16 +3,13 @@
 #include <iostream>
 
 class Animal {
-public:
-	float weight;				// kg
-};
+	private:
+		float weight;				// kg
 
-class Mammal : public Animal {
-public:
-	float pregnancyDuration;	// days
-};
+	public:
+		const float getWeight() const { return weight; }
+		void setWeight(const float v) { weight = v; }
 
-class Cat : public Mammal {
-public:
-	float vibrissaLength;		// meters
+	protected:
+		Animal(const float w) { weight = w; }
 };
diff --git a/animals/bird.h b/animals/bird.h
new file mode 100644
index 0000000..bd24c05
--- /dev/null
+++ b/animals/bird.h
@@ -0,0 +1,50 @@
+#pragma once
+
+#include "animal.h"
+
+class Bird : public Animal {
+    private:
+	    float wingLength;       // meters
+    public:
+        const float getWingLength() const { return wingLength; }
+		void setWingLength(const float v) { wingLength = v; } 
+    protected:
+        Bird(const float wl, const float weight) : Animal(weight) { wingLength = wl;}
+};
+
+class Eagle : public Bird {
+    private:
+        float visionStrength;   // between 0 and 1 
+    public:
+        Eagle(const float vs, const float wl, const float weight) : Bird(wl, weight) { 
+            visionStrength = vs;
+        }
+        const float getVisionStrength() const { return visionStrength; }
+		void setVisionStrength(const float v) { visionStrength = v; } 
+};
+
+class Parrot : public Bird {
+    private:
+        int plumageColor;       // int in 16 base (5570463 -> #54ff9f)
+    public:
+        Parrot(const int pc, const float wl, const float weight) : Bird(wl, weight) { 
+            plumageColor = pc;
+        }
+        const int getPlumageColor() const { return plumageColor; }
+		void setPlumageColor(const int v) { plumageColor = v; } 
+
+};
+
+std::ostream& operator << (std::ostream& os, const Parrot& p) {
+    os << "parrot's color: " << p.getPlumageColor() << std::endl;
+    os << "parrot's wing length: " << p.getWingLength() << std::endl;
+    os << "parrot's weight: " << p.getWeight() << std::endl;
+    return os;
+}
+
+std::ostream& operator << (std::ostream& os, const Eagle& e) {
+    os << "eagle's vision strength: " << e.getVisionStrength() << std::endl;
+    os << "eagle's wing length: " << e.getWingLength() << std::endl;
+    os << "eagle's weight: " << e.getWeight() << std::endl;
+    return os;
+}
\ No newline at end of file
diff --git a/animals/mammal.h b/animals/mammal.h
new file mode 100644
index 0000000..c5dbe4d
--- /dev/null
+++ b/animals/mammal.h
@@ -0,0 +1,66 @@
+#pragma once
+
+#include <iostream>
+#include "animal.h"
+
+class Mammal : public Animal {
+    private:
+	    float pregnancyDuration;	// days
+    public:
+        const float getPregnancyDuration() const { return pregnancyDuration; }
+        void setPregnancyDuration(const float d) { pregnancyDuration = d; }
+    protected:
+        Mammal(const float pd, const float weight) : Animal(weight) {
+            pregnancyDuration = pd;
+        }
+};
+
+class Cat : public Mammal {
+    private:
+	    float vibrissaLength;		// meters
+    public:
+        Cat(const float vl, const float pd, const float weight) : Mammal(pd, weight) { 
+            vibrissaLength = vl; 
+        }
+        const float getVibrissaLength() const { return vibrissaLength; }
+        void setVibrissaLength(const float v) { vibrissaLength = v; }
+};
+
+enum Breed { Sharpey, Terier, Chauchau };
+
+class Dog : public Mammal {
+    private:
+        Breed breed;
+	public:
+        Dog(const Breed b, const float pd, const float weight) : Mammal(pd, weight) { 
+            breed = b; 
+        }
+        const Breed getBreed() const { return breed; }
+        void setBreed(const Breed b) { breed = b; }
+
+        const std::string getBreedAsString() const {
+            std::string strBreed = "";
+            switch (breed) {
+                case Sharpey: strBreed = "sharpey"; break;
+                case Terier: strBreed = "terier"; break;
+                case Chauchau: strBreed = "chau chau"; break;
+            }
+
+            return strBreed;
+        }
+};
+
+std::ostream& operator << (std::ostream& os, const Cat& c) {
+    os << "cat's vibrissa length: " << c.getVibrissaLength() << std::endl;
+    os << "cat's pregnancy duration: " << c.getPregnancyDuration() << std::endl;
+    os << "cat's weight: " << c.getWeight() << std::endl;
+    return os;
+}
+
+std::ostream& operator << (std::ostream& os, const Dog& d) {
+    
+    os << "dog's breed: " << d.getBreedAsString() << std::endl;
+    os << "dog's pregnancy duration: " << d.getPregnancyDuration() << std::endl;
+    os << "dog's weight: " << d.getWeight() << std::endl;
+    return os;
+}
\ No newline at end of file