Here again, none of those things are a real accurate judge of age. Some males learn to
black beard earlier than others. My first male started the
blackbearding, headbobbing at about 7 months, Assassin learned how to do this a few weeks ago, around 5 months. The pores on his inner thighs are already quite large, and again, my first males become prominant around 7 to 8 months. The spikes become longer, fuller and each spike thicker as they approach adult hood(1 year to 18months). Assassin already has some pretty large spikes, but it's still filling in. All of these things combined on an adult are more easily discernable, but how early each of these things happens really depends on the dragon itself.