Jurassic Park - Operation Genesis cheats and cheat codes for XBox

Cheat mode:
While playing game, enter the following button combination cheats:
Note: Do not select anything before entering the codes. 
The cheat may will not work with an item selected.

No Red Tape
Press L, R, Left, Down, Down, Down, Down.

Extinction Event (kill all dinosaur)
Press L, R, Down, R, L.

Twister reach the island:
Press Left, Up, Right, Down, L + R.

Disable Twisters
During game play, hold L + R and press Left, Right. Release L + R, after 
press L + R again. 
or
press Left, Right, L, R

Stormy weather
Press R, R, L, R, Down, Up, Down.

Heat wave:
Press R + Down, R + Down.

Zombie dinosaurs:
Press R, R, R, L, Right.

Rampage Time (stressed carnivores)
Press L, L, L, Left, Left, Left.

Shoot from safari cars:
Press R + L, Left, Down, Right, Right.

Set dinosaurs DNA to 55%
Press Down, R + Up.

Set dinosaurs DNA to 100%
Press R, Up, R, Right, L, Down.

Additional $10,000
Press L + Up, L + Down

Finances reduced to 0:
Press L + R, Down.
or
Press L, R, L, R, Down, Down

Guaranteed dinosaur immunity
During game play, hold L + R and repeatedly press Up.
or 
press Up, Up, R, L, Up, Up

All tourists die:
During game play, hold R and press Right, Left, Right, Left, Right. 
or
Press Left, Right, Left, Right, R

Blow up safari cars
During game play, hold L + R and repeatedly press Up, Down, Up, Down. 
or
Press R, L, Up, Down, Up, Down

Select digsites without stars:
Press Left, Down, Right, Up, L + R, L + R.

Unlock all missions, exercises, and Site B
Press R, Right, Right, Right, Right, R. 

Non-tested cheats:

Market Day
Press L + R + Down

Unlock all research
Press Down, Down, Down, Left, Right, L, Down, Up.

$250,000
During game play, press L, Right, Right, L, R, Down

Increase park rating by one star:
During game play, press Right, L, Up, L, L, Down

Park with 3 Stars:
During game play, Press L, R, Down, Down, L, Right 

Sick dinosaur:
During game play, Press Down, Up, Down, Left, R, R, R

No more rampage:
During game play, Press L, Left, Up, Left, Up, Left, L

Exodus:
Set dinosaur DNS to 0%
During game play, Press L, R, L, Right, Down, R

End of storm:
During game play, Press R, R, Left, Right, Up, Right 

Happy visitors:
During game play, Press R, Down, L, Up, Up, Up

Low securtity fences:
During game play, Press Down, Down, Left, Right, L, L, Up, Up

High securtity fences:
During game play, Press L, Left, Left, R, R, Right

Destroy all fences:
During game play, Press Up, R, Down, L, Left, Left

All path damaged:
During game play, Press Right, Right, R, R, L, Down

Unlock Site B option in main menu:
Finish all missions

More visitors
Build 4 or 5 entrances on all different sides.

T-Rex: DNA:
To get some T-Rex DNA, unlock Judith River Formation B and put your dig 
teams there. They will find T-Rex remains.