How often Predators arrive for their feasting ritual on xenomorphs and humans ?
368470
I think they come once everytime a precession of the equinoxes is complete which means once every 2100 years or so. This is also the time taken for us to complete one full cycle of the Zodiac. The precession of the equinoxes was very important to the ancient Mayan civilisation and the filmakers seemed to get the idea for Alien vs Predator from there.
455290
I think they are rotating them around to the different schools so that no one will know that they are actually aliens from the planet Zenon commisioned by our government to torture and torment the young into submission. These creatures actually do not have a face but must paint it on every morning in an attempt to look human but obviously fail. These beasts may live to be 1,000 years old and feed on cats and oat bran. Many usually raise or capture their own cats but there are many "cat ladies" (also aliens) that raise them for sale to such beings. \n\nCurrently the government denies such activity but activist groups such as MAAT (Mothers Against Alien Teachers) are working round the clock to bring to light this insideous plot against our youth and Americans in general. Althought MAAT works in secrecy you can help the movement by being alert and watchful for the aliens. Any "person" holding a ruler, wearing glasses, having beehive haircuts, and having the indicitive "chicken skin" neck tissue is most likely a Zenon alien. They also may or may not have and hair on their chins or in their noses and ears...Usually though if you notice these last few indicators it's too late...
73156
They just breed the virus, AFAIK.  Mutations pop up in every generation. In fact, as a matter of comparison, humans - on average - have about 60 mutations.
479915
Creatures from beyond Earth!
790686
They get bored after a while and find other prey.  Predators are like that.\n\nReport them if they are offensive.\n\nReply to every violation notice you get because of their false reporting.\n\nPost a blog on the forum.  Or add to the ones that are there.
599686
Female anacondas do not devour the males!\n\n- Praying mantis\n- Many spiders\n- Ceratopogonid midges\n\nhttp://www.yesbutnobutyes.com/archives/ugly_animal_kingdom/index.html\n\n---------\nUpdate: An interesting article that discusses adaptive and nonadaptive hypotheses for sexual cannibalism in spiders.  The evidence suggests that, at least in spiders, there's a connection between foraging decisions and cannibalistic behaviour towards males. \nhttp://www.blackwell-synergy.com/links/doi/10.1046/j.1420-9101.2002.00363.x/full/\n(let me know if you cannot download the article)
910504
The humans are interesting to watch, especially if its feeding time or mating season.  I love to watch them stuff their faces full of food.  Odd creatures, yet fascinating.  If not them, see the primates first.  They seem to be the most active.
16159
It depends on the species. Some will travel very far to follow, or find, food. Some will travel during different seasons.
808846
hunting  predators  !  Being   spotted  and ambushed   can be fairly easy. That is exotica to onlookers' eyes  to have gotten to learn  by seeing  how  a  primitive  performance  will  have  looked  like .
72636
Well, here in Argentina they are eaten by birds of prey (eagles and such) and large carnivores such as cougars. \nOf course, when speaking of "natural enemies" we all tend to think of predators. But we all have other, smaller natural enemies: parasites (ticks, lice, worms) and diseases (rabies, hantavirus, etc).
578763
some dig holes, have a trap door, waith until prey comes along, and the grabs them...\n\nothers hunt by going out..
284515
The manner in which the aliens breed is going to be the same regardless of what species they breed with.  Yes, the alien baby will take on certain aspects of it's birth parent; however it will never not have acid for blood or not shed skin as it grows or not have a double mouth or not breed through laid eggs.  Therefore it's a dominant species with absorbs only the physical genetic aspects of a host.  It is and always will be an alien.  It might look a little like a predator but it's an alien.
825863
Once a year.  They grow them in the summer and fall, and shed them after mating season.
487365
adaptive significance of coprophagy
48962
It depends on how big each of those are, not the appetite. Most spiders will eat and eat, no matter how full they are, because their abdomen will just continue to expand. But on average, I would say about 1. It takes at least an hour for spiders to eat something.
829593
All crustaceans are opportunistic in there feeding habits
330434
All those listed would be able to do this job Nicely. My favorite--Velociraptors. Oh for the love of a good chase!! The velociraptors would have her running on those tooth-pick legs of hers and she'd probably break both in the chase, fall and "CRUNCH"!! It's Din-Din Time, They might need to spit on her first before eating--Gets that bitter taste out of the Velociraptors mouths,LOL!!!!!!!!!!!!!!!