#burdles

~Note: this is relatively small, and consists of fan-theories as it were. So hopefully it doesn’t count as plagiarism but if so I will take it down~

Over time on Serina some birds have changed so much that they hardly count as birds at all. In the Linnaeic system (which has been mentioned early on in the project) I would say (at least!) two lineages are not birds.

They are the changelings and the burdles.

The somewhat official definition of birds is that they tend to fill these descriptions:

·         Feathers

·         toothless beaked jaws

·         the laying of hard-shelled eggs  

·         a high metabolic rate

·         a four-chambered heart

·         a strong yet lightweight skeleton

With the changelings, I don’t think I need to explain myself, but as for the burdles:

               They don’t have feathers, and at least some of them have a slow metabolic rate. At least one burdle, the riverine muckodile, has ‘teeth’.

To specifically lay out the class characteristics (like I did above for the birds), burdles are:

·         Featherless – thick scaly skin

·         toothless beaked jaws

·         Aquatic (though air-breathing)  

·         Mesothermic (though some are ectothermic)

·         a four-chambered heart

·         a strong yet lightweight skeleton

Class characteristics for the changelings:

*         Have a metamorphic development from larva to adulthood. In some                    clades the larva is retained as an embryo in the body, prior to being born              (placentalism).

*         Some have toothless beaked jaws

*         Small, soft-shelled eggs, of which many tend to be laid at a time

*       A wide variety of metabolic rates – some are fully ectothermic but others              are endothermic while adults

I would also consider lumberbeests a new Linnaeic class, but as they consist of only one genus, they are not marked on the chart.