Some notes on evolutionary levels

-Starters:

Gen I: 16, 16, 16--32, 36, 36
Gen II: 16, 14, 18--32, 36, 30
Gen III: 16, 16, 16--36, 36, 36
Gen IV: 18, 14, 16--32, 36, 36
Gen V: 17, 17, 17--36, 36, 36
Gen VI: 16, 16, 16--36, 36, 36
Gen VII: 17, 17, 17--34, 34, 34

Lowest level is 30, highest level is 36 for final evolutions.

For first evolutions, lowest level is 14, while the highest level is 36.
15 is unused for first evolution. 31, 33, 35 are unused for second evolutions.

There are no group of starters that start evolving at Level 14.

My personal guess would as such though:

Gen 8: 16, 16,16--34, 34, 34
Gen 9: 17, 17, 17--32, 32, 32
Gen 10: 16, 16, 16--32, 32, 32
Gen 11: 16, 16, 16 -- 30, 30, 30
Gen 12: 15, 15, 15 -- 30, 30, 30
Gen 13: 15, 15, 15 -- 28, 28, 28
Gen 14: 14, 14, 14 -- 28, 28, 28
Gen 15: 19, 19, 19 -- 36, 36, 36
Gen 16: 18, 18, 18 -- 36, 36, 36

-Early bugs:

Gen I: 7->10->+
Gen II: 18, 22
Gen III: 7->10->+
Gen IV: 10, 20
Gen V: 20->hap->+, 22->30->+
Gen VI: 9->12->+
Gen VII: 20->terrain->+, 25

Level 8 and 11 are unused for cocoons. Higher cocoons evolve at Level 20 first. 10-18 has not been used by weaker bugs.

My overall guess is:

Gen 8: Cocoon, 9 to 12.
Gen 10: Higher cocoon. 22 and later.
Gen 9: Cocoon. 11 to 14
Gen 10: Higher cocoon: 22 and later.
Gen 11: Cocoon. 11 to 14
Gen 12: Higher cocoon. 24 and later.
Gen 13: Cocoon. 13 to 16.
Gen 14: Higher cocoon. 24 and later.

-Early birds:

Gen I: 18->36, 20
Gen II: 20
Gen III: 22, 25
Gen IV: 14->34
Gen V: 21->32
Gen VI: 17->35
Gen VII: 14->28

19, 15, 16, and below 14 are not used. 21, 23 and 24 are also unused.

Personal guess would be:

Gen 8: 21->31
Gen 9: 16->33
Gen 10: 15->30
Gen 11: 20->30
Gen 12: 15->31
Gen 13: 16->32
Gen 14: 19->29
Gen 15: 14->29
Gen 16: 17->34

-Psuedo legendaries:

-Gen I: 30->55
-Gen II: 30->55
-Gen III: 30->50, 20->45
-Gen IV: 24->48
-Gen V: 50->64
-Gen VI: 40->50
-Gen VII: 35->45

Lowest bound for first stage is 20. Highest is 50. Lowest bound for the second stage is 45. Highest is 64.

(Note: Axew covers 38->48).

My personal guess is:

Gen 8: 30->40
Gen 9: 23->45
Gen 10: 45->59
Gen 11: 45->55
Gen 12: 35->45
Gen 13: 25->35
Gen 14: 25->50
Gen 15: 40->54


-Fossils:

Gen I: 40
Gen III: 40
Gen IV: 30
Gen V: 37
Gen VI: 39

My personal guess is:

Gen 8: 39
Gen 9: 29
Gen 10: 36
Gen 11: 38
Gen 12: N/A
Gen 13: 38
Gen 14: 28
Gen 15: 35
Gen 16: 37
Gen 17: N/A
Gen 18: 37
Gen 19: 27
Gen 20: 34
Gen 21: 36
Gen 22: N/A
Gen 23: 36
Gen 24: 26
Gen 25: 33
Gen 26: 35

-Overall for second stagers:

Highest
Gen I: 40
Gen II: 38
Gen III: 42
Gen IV:  40
Gen V: 59
Gen VI: 48
Gen VII: 42

Lowest:
Gen I: 20
Gen II: 15
Gen III: 15
Gen IV: 10
Gen V: 20
Gen VI: 20
Gen VII: 20

-Overall for third stagers:

Highest:
Gen I: 30->55
Gen II: 30->55
Gen III: 30->50
Gen IV: 24->48
Gen V: 50->64
Gen VI: 40->50
Gen VII: 43->53, 35->45

Lowest:
Gen I: 7->10
Gen II: H->18, 18->27
Gen III: 7->10
Gen IV: 15->30
Gen V:  21->32, 16->32
Gen VI: 9->12
Gen VII: 14->28