Sentence:  She fell asleep leaning on her hand , hearing the house creaking as though it were a living a private life of its own these two hundred years , hearing the <WSD>birds</WSD> rustling in their cages and the occasional whirring of wings as one of them landed on the table and walked across the newspaper to perch in the crook of her arm . 
Meaning of the word marked with <WSD> tags:  warm-blooded egg-laying vertebrates characterized by feathers and forelimbs modified as wings