Edited by Silas Eckhardt, some rights reserved (CC BY-SA)
Photo Credits
- 1. (c) Tracey Fandre, some rights reserved (CC BY-NC-ND), uploaded by Tracey Fandre
- 2. (c) Mike Quinn, Austin, TX, some rights reserved (CC BY-NC), uploaded by Mike Quinn, Austin, TX
- 3. (c) Aaron Lincoln, some rights reserved (CC BY-NC), uploaded by Aaron Lincoln
- 4. (c) Valtierra, some rights reserved (CC BY-NC-ND), uploaded by Valtierra
- 5. (c) Alberto González, some rights reserved (CC BY-NC), uploaded by Alberto González
- 6. (c) José Belem Hernández Díaz, some rights reserved (CC BY), uploaded by José Belem Hernández Díaz
- 7. (c) victor rodriguez, some rights reserved (CC BY-NC), uploaded by victor rodriguez
- 8. (c) Simon Kingston, some rights reserved (CC BY-NC), uploaded by Simon Kingston
- 9. (c) Chuck Sexton, some rights reserved (CC BY-NC), uploaded by Chuck Sexton
- 10. (c) Lena Zappia, some rights reserved (CC BY-NC), uploaded by Lena Zappia
- 11. (c) Robert Lord Zimlich, some rights reserved (CC BY-NC), uploaded by Robert Lord Zimlich
- 12. (c) Catherine C. Galley, some rights reserved (CC BY-NC), uploaded by Catherine C. Galley
- 13. (c) Shahan Derkarabetian, some rights reserved (CC BY-SA), uploaded by Shahan Derkarabetian
- 14. (c) joshuasexton, some rights reserved (CC BY-NC-ND), uploaded by joshuasexton
- 15. (c) Pedro Alanis, some rights reserved (CC BY-NC), uploaded by Pedro Alanis
- 16. (c) Laura Gaudette, some rights reserved (CC BY), uploaded by Laura Gaudette
- 17. (c) Bob O'Kennon, some rights reserved (CC BY-NC), uploaded by Bob O'Kennon
- 18. (c) Lee Hoy, some rights reserved (CC BY-NC-ND), uploaded by Lee Hoy
- 19. (c) James Bailey, some rights reserved (CC BY-NC), uploaded by James Bailey
- 20. (c) Ken-ichi Ueda, some rights reserved (CC BY), uploaded by Ken-ichi Ueda
- 21. (c) Francisco Farriols Sarabia, some rights reserved (CC BY), uploaded by Francisco Farriols Sarabia
- 22. (c) C. Mallory, some rights reserved (CC BY-NC), uploaded by C. Mallory
- 23. (c) Jeff McIntyre, some rights reserved (CC BY-NC), uploaded by Jeff McIntyre
- 24. (c) Steven Mlodinow, some rights reserved (CC BY-NC), uploaded by Steven Mlodinow
- 25. (c) John Trent, some rights reserved (CC BY-NC-ND), uploaded by John Trent
- 26. (c) Jon McIntyre, some rights reserved (CC BY-NC), uploaded by Jon McIntyre
- 27. (c) Matthias Buck, some rights reserved (CC BY-NC), uploaded by Matthias Buck
- 28. (c) Gordon C. Snelling, some rights reserved (CC BY), uploaded by Gordon C. Snelling
- 29. no rights reserved, uploaded by Rod
- 30. (c) Todd Fitzgerald, some rights reserved (CC BY-NC), uploaded by Todd Fitzgerald
- 31. (c) ellen hildebrandt, some rights reserved (CC BY-NC), uploaded by ellen hildebrandt
- 32. (c) taharms48, some rights reserved (CC BY-NC), uploaded by taharms48
- 33. (c) fydnar, some rights reserved (CC BY-NC), uploaded by fydnar
- 34. (c) Masumi Palhof, some rights reserved (CC BY-NC), uploaded by Masumi Palhof
- 35. (c) jessica_garcia, some rights reserved (CC BY-NC), uploaded by jessica_garcia
- 36. (c) Crowdy Pollock, some rights reserved (CC BY-NC), uploaded by Crowdy Pollock
- 37. (c) Ted MacRae, some rights reserved (CC BY-NC), uploaded by Ted MacRae
- 38. (c) Arturo Santos, some rights reserved (CC BY), uploaded by Arturo Santos
- 39. (c) Jason M Crockwell, some rights reserved (CC BY-NC-ND), uploaded by Jason M Crockwell
- 40. (c) Marshal Hedin, some rights reserved (CC BY-NC-SA), uploaded by Marshal Hedin
- 41. (c) Tom Palmer, some rights reserved (CC BY-NC), uploaded by Tom Palmer
- 42. (c) Evan M. Raskin, some rights reserved (CC BY), uploaded by Evan M. Raskin
- 43. (c) Millie Basden, some rights reserved (CC BY), uploaded by Millie Basden
- 44. (c) Ashley Schmitz, some rights reserved (CC BY-NC), uploaded by Ashley Schmitz
- 45. (c) Joel DuBois, some rights reserved (CC BY-NC), uploaded by Joel DuBois
