| Monogamy | Two birds form a pair bond and work together to brood and care for young |
| Polygyny | Male attracts and mates with many females. The male builds nest and females cares for young. |
| Polyandry | Female attracts and mates with many males |
| Polygnandry | Female pair bonds with multiple males and vice versa |
| Promiscuity | Each female can mate with multiple males and vice versa |
| Extra Pair Copulation | Bonded pair exists but male and female mate with others |
| Methods used for attraction | Dance displays, food delivery, mutual preening, singing |
| Songs | Longer and usually for territory or courtship |
| Calls | Shorter and for contacting one another |
| How do birds vocalize | Air comes through the windpipe causing the membrane to vibrate and make sound |
| What focalization piece is different | The syrinx |
| How do birds learn their songs | They learn from a tutor then repeat till memorized |
| Cup nest | Nest shaped like a bowl |
| Cup nesters | Robins and humming birds |
| Scrape nest | Digging away a depression in the ground and adding stones and leaves |
| Scrape nesters | Lapwings and plovers |
| Burrow | Shelters in the ground |
| Borrowers | King fishers and burrowing owls |
| Cavity nest | Chamber in hallowed tree |
| Cavity nesters | Woodpeckers and barbets |
| Platform nest | Large nest lined with clay for large birds |
| Platform nesters | Eagles and storks |
| Materials for building nests | Mud, twigs, branches, leaves, moss, grass, feathers, and pine needles |
| Step one of egg development | Egg is released from ovary and spends 30 minutes in the infundibulum |
| Step two of egg development | 3 hours spent in magnum region where the albumen is laid |
| Step three of egg development | 1 hour in isthmus region where the shell membranes are produced |
| Step four of egg development | 24 hours in uterus where the hard shell forms and egg get pigmentation |
| Part of the egg | Shell, membranes, albumen, chalaza, and yolk |
| Nutrients of eggs | 21% lipids and 16% proteins |
| Categories of hatchlings | Precocial and altricial |
| Precocial | Mobile, sighted, varying degree of parental care |
| Examples of precocial chicks | Canada goose, wood duck, and killdeer |
| Altricial | Non-mobile, blind, extra parental care, and nest bound |
| Examples of altricial chicks | American robin, bald eagle, and blue jay |
| How do birds find food | Sense of smell, by memory, and through observation |
| Different categories for foraging | Chasing, ambushing, tools, grazing, and probing |
| Behaviors to alert predators | Alert calls and mobbing |
| Number of birders | Tens of millions |
| Amount that borders contribute | $20 billion |
| Main threats for vulnerability | Urbanization, deforestation, climate change, disease, invasive species, and hunting and trapping |
