Question

Mythical horse phylogeny: For the following questions imagine that all of these different types of mythical horses existed and were evolutionarily related to modern day real horses. I have included the descriptions just to help make the organisms a little more understandable. The key information that you need is all in Table 1 though so don't worry too much about the descriptions. Unicorn: A magical forest dwelling horse with a single horn on its head. These creatures are herbivores that are most active just after dawn and just before dusk. Their hooves have an outer covering of precious metal either gold or silver depending on the breed. Pegasus: A magical horse found mostly on the open plains these creatures have large magnificent wings that allow them to fly. They are herbivores that are active throughout the day except for the hottest part of the hottest days where they tend to prefer to find cool shade to wait out the heat. Their hooves are actually covered on the outside with precious metal like the unicorn but in this case the metal is platinum. Zombie horse: A fierce predator found in the mountains and foothills these horses are carnivores that hunt mostly prey from the size of rabbits to coyotes. They have large prominent fangs and come out only at night since they rapidly deteriorate if exposed to sunlight. Vampire horse: Thankfully the vampire horse is an extremely rare and solitary creature. Living mostly in dark caves underground they are carnivores with a pair of large fangs that can drain the blood of a large deer or cow in just a few minutes. Like the zombie horse these organisms are killed by exposure to sunlight and so are commonly found in the darkest parts of the night. Dragon horse: A recently discovered species found in the forests that cover islands in Indonesia and the Philippines. These small carnivores fly through the air with wings and hunt the large numbers of insects that come out at night with tiny needle like fangs. Other than their wings these creatures lack any other appendages and on the ground must move their bodies with snake like slithering. Table 1: phylogenetic characters of mythic horses Real horse Unicorn Pegasus Vampire horse Zombie horse Dragon horse 1 11 4-legs Invisible to humans 1 Carnivorous 1 Fangs OT O 0 0 1 1 Killed by sunlight Wings 0 1 0 1 0 1 Precious metal hooves Horn 1 O

Answer 1

11) At first, we look for the traits that are shared between the largest number of organisms. We find that, 4-legs characteristic is an ancestral trait (As it is present in the real horse) & shared by maximum number of organisms. Next, we look for the characteristic that is shared by largest number of organisms after 4-legs. We find that this is the trait invisible to humans. Based on this, we started our tree drawing & this is shown below.

Real Horse 4-legs Invisible to humans

Now, we look for the next largest shared trait. The traits carnivorous & fangs are shared by 3 organisms. The traits are not shared by Unicorn & Pegasus. So, they must be branching off before appearing these traits. Also, individual traits that appeared in them (Horn & precious metal hooves in Unicorn; Wings & precious metal hooves in Pegasus) is placed on their lineage. This is shown below.

Pegasus Precious metal hooves Unicorn Real Horse Precious metal hooves Wings Fangs Carnivorous Hom 4-legs Invisible to humans

Next, we look for largest shared trait. The trait 'killed by sunlight' is shared by two organism. This trait is not shared by Dragon horse. So, they must be branching off before appearing this trait. Also, individual traits that appeared in them (Wings & lost 4-legs) is placed on their lineage. Based on this the final tree is drawn below.

Vampire Horse Dragon Horse Zombie Horse Lost 4-legs Pegasus Precious metal hooves Wings Killed by sunlight Unicorn Real Horse Precious metal hooves Wings HTLI Fangs Carnivorous Hom 4-legs Invisible to humans