Hello Jim Wilson,
I have some questions for you.
Male Ouessant Ram 20KG VS Male German Shepherd 30KG.
Male Anteater 35KG VS Male Human 80KG (Trained en Strong).
Male Striped Hyena 40KG VS Male Strongest dog type and same weight.
Male Striped Hyena 40KG VS Male Grey Wolf 50KG.
Male Striped Hyena 40KG VS Male Human 80KG (Trained en Strong).
Male Spotted Hyena 40KG VS Male Human 80KG (Trained en Strong).
Female Spotted Hyena 90KG VS Male Leopard 70KG.
Female Spotted Hyena 90KG VS Female Lionnes 80KG.
2 Male Giant Otter 30KG VS Male Jaguar 70KG (In water).
Male Giant Otter 30KG VS Male Human 80KG (Trained en Strong).
Male Polar Bear 600KG VS Female Leopard Seal 500KG (In water).
Male Polar Bear 800KG VS 2 Male Lions (Each 200KG) and 2 Female Lioness (Each 140KG).
Male Grizzly Bear 500KG VS 2 Male Lions of 200KG.
Male Kodiak Bear 850KG VS 5 Female Lioness each 140KG.
I appreciate very much that you take the time and effort to answer my questions.
* not sure if you meant for this one to come to me, but I'll answer it anyway *
Male Ouessant Ram 20KG VS Male German Shepherd 30KG: The ram may have large horns, but a sheep isn't on the same level (pound-for-pound) as, let's say, a sable antelope or a mountain goat. The German Shepherd will have a decent weight advantage, will have better lateral movement, and possibly a lot more aggression. The mentality of each animal will be important here, and I don't think the ram will have the moxie to repel a quicker, bolder animal with a decent set of jaws and a 50% weight advantage. German Shepherd wins.
Male Anteater 35KG VS Male Human 80KG (Trained en Strong): This will depend on the level of training the human possesses (in regards to proper spacing, skill in offensive arsenal, mentality, etc.). A human trained to fight is trained to excel in combat against another human, not an anteater. Anteaters have very sharp claws that can be dangerous when they're defending themselves, and can sometimes repel jaguars & cougars with aggressive resistance. If the human employs an attack that takes advantage of reach (like kicking), the human will have a chance to succeed. The weight advantage of the human is a great asset here, but he'll need to bring more to the table than size to keep from getting shredded. Depends on the level of training. Some humans may succeed; others will not.
Male Striped Hyena 40KG VS Male Strongest dog type and same weight: Striped hyenas are tough, feisty mammals with strong bites. They occasionally drive larger predators away in confrontations. By "strongest dog type" I'll assume you mean most formidable pound-for-pound in this weight range as a combatant (and not to use only physical strength as a measure). American pit bull terriers are right at the top of the list. These dogs, sad to say, have been used at times to fight, and the "game bred" ones have the right combination of assets (strength, athleticism, stamina, tenacity, durability, etc.) to be very good at it. An APBT at 40kg will be about 10kg over it's most effective weight, but will still be a very powerful adversary for anything in its weight range. A battle with a striped hyena will be a bite vs bite affair, but the way the APBT employs its bite (rushing in, grabbing the head/face area, shaking & pulling, ignoring injury) will be a difficult technique for the hyena to counter. No regular pet dog will consistently defeat a striped hyena at equal weights, but a trained one certainly can. I favor a trained American pit bull terrier to succeed more times than not, and other breeds in this weight range (Japanese Tosa, Gull Terr, Bull Terrier, etc.) have a chance as well. Check out the entry "most interesting animal fights" from 8/11/2013; I addressed this matchup there (section "H").
Male Striped Hyena 40KG VS Male Grey Wolf 50KG: Striped hyenas are bold & aggressive, and can usually drive a wolf away in an actual encounter. However, if a gray wolf is determined to fight, it will have a decent chance. Wolves are nimble, and have strong bites, but they are better suited for confrontation when joined with other members of the pack. Striped hyenas have strong bites as well (and it may be just as strong as the wolf's despite its smaller size). The striped hyena will probably need to be at least 85% of the wolf's weight to give it an even contest, and it's not quite there in this scenario. Close fight, but edge to the gray wolf.
Male Striped Hyena 40KG VS Male Human 80KG (Trained en Strong): While the level of training may make a difference in how close this fight will be, I don't think a human will succeed without the aid of a weapon. Trained humans aren't trained to engage in battle with a hyena, and a bite or 2 from this tough-as-nails animal will test the resolve of the highest levels of mental toughness. The human won't likely have a good enough level of offense to compete with the striped hyena, and won't have an adequate enough level of defense to repel the bites of this aggressive animal. A human may succeed on occasion, but the striped hyena will be the victor on most occasions.
Male Spotted Hyena 40KG VS Male Human 80KG (Trained en Strong): Spotted hyenas are a level above striped hyenas, and one will have a field day with a human on most occasions. Spotted hyenas deal with conflict on a regular basis (lions, leopards, African wild dogs, various herbivores), and have good endurance & durability. The jaw strength of a spotted hyena is high enough to crush bones at a carcass, and even a trained human will have trouble countering the hyena's teeth being sunk into an extremity. A highly-trained individual (Navy seal, Olympic athlete, MMA fighter, etc.) might get "lucky" on occasion, but the spotted hyena is heavily favored here.
Female Spotted Hyena 90KG VS Male Leopard 70KG: Spotted hyenas are very durable, have good endurance, and very strong bites (can crush bones at a carcass). They are somewhat ungainly in their movements, and are more comfortable entering a conflict with other members of the clan (as opposed to solo). Leopards have the typical big cat attributes (speed, agility, athleticism, jaws & claws, killing know-how) and are very powerful (can drag heavy prey items into trees). Like many solo predators, leopards won't readily engage in a serious conflict unless something important is at stake. An injury will hamper the leopard's ability to hunt, and it knows this. In a realistic confrontation, a spotted hyena with this much of a weight advantage will drive the leopard away. However, if the leopard is infused with a high level of determination (perhaps in a case where a fight to the death is unavoidable), it will have the assets to give it the slightest of edges (but will likely be injured). Check out entries "None" from 10/31/13 and "question" from 11/28/2013 for more detail.
Female Spotted Hyena 90KG VS Female Lioness 80KG: These 2 are no strangers to one another. Spotted hyenas are durable, have good endurance, & strong bites. Lionesses are battle-tested cats that hunt in groups, occasionally overpowering dangerous prey items like zebra & Cape buffalo. In a spotted hyena vs lioness battle, the spotted hyena will have better endurance & stronger bite, but the lioness will have the advantage in speed, agility, & overall weaponry (presence of claws/paw usage). Big cats pack a lot of explosive action into a small window of time, but usually have the assets to accomplish their goals before they succumb to fatigue. A spotted hyena may occasionally drive the lioness away in a realistic encounter, but won't prevail most of the time in a down & dirty fight. A lioness can use her agility & quickness to get into a favorable position to land a killing bite on the spotted hyena, and should be able to neutralize the hyena's crushing bite (its only weapon) on most occasions. Hyenas are durable & difficult to kill, but a lioness has the tools to succeed (even against a larger hyena). Lioness wins.
2 Male Giant Otter 30KG VS Male Jaguar 70KG (In water): Giant otters are fantastic swimmers, and have strong bites with sharp teeth. Jaguars are among the strongest of cats (pound-for-pound), have huge heads with powerful jaws (can bite through turtle shells, caiman armor, & skulls), and won't hesitate to engage in a water battle. If the water is shallow enough to enable the jaguar to touch the bottom & keep its head above water, it will have a good chance to prevail. The otters will be more maneuverable in the water, but will need to come close to the jaguar to apply their bites. The jaguar should be quick enough to capture one of the otters (and kill it quickly) before it receives too many serious bites, and then will focus on the remaining otter to seal the victory. If the water is too deep, however, the jaguar won't be able to apply its offense as adequately, and will be in a more difficult situation. As long as the water's not too deep, the jaguar wins.
Male Giant Otter 30KG VS Male Human 80KG (Trained en Strong): This depends on a couple of things (level of human's training/location of battle). An otter isn't nearly as mobile on land as it is in the water, and a human with the right level of experience & physical prowess might have a chance (probably with well-placed kicks & proper distancing). An otter's bite can cause serious injury to a human. I recently spoke with a zookeeper in front of the otter exhibit who stated that one must be careful feeding an otter because it will "tear you up". A battle where the otter has access to water will weigh heavily in its favor. The otter will be too agile for the human to apply any effective offense, and the bites from this mustelid will be hard to defend. Overall edge to otter.
Male Polar Bear 600KG VS Female Leopard Seal 500KG (In water): Depends on the water depth to a degree. Polar bears are massively powerful ursids with strong jaws & sharp claws, and occasionally predate upon walruses. Leopard seals are aggressive predators with formidable jaws armed with teeth measuring up to 2.5cm in length (with which they can shred a penguin). If the water is shallow enough to enable the polar bear to move with minimal limitation & prevent the leopard seal from achieving adequate mobility, the polar bear will win more times than not (by using its forelimbs to control movement, claws to grab/tear, jaws to deliver bites). If the water is deep enough to allow the leopard seal to swim freely (which will limit the bear's ability to move quickly or apply force properly), the seal will have the advantage. Edge to polar bear in shallow water; leopard seal favored in deeper water.
Male Polar Bear 800KG VS 2 Male Lions (Each 200KG) and 2 Female Lioness (Each 140KG): The polar bear is a massively powerful ursid with great endurance, durability, & weaponry (jaws & claws). Lions work well together when hunting, and that will aid them in this conflict. However, the polar bear will have a huge advantage in strength, and will have the ability to quickly injure any of the cats to decrease their numbers advantage. The lions will need to use their quickness, agility, & finishing know-how with precision to have a decent chance. Bears can fight back better than the majority of typical lion adversaries (supple bodies/usable forelimbs/bites/paw swipes), and a polar bear will have the stamina to battle strongly when the lion's endurance begins to wane. Big cats can operate very effectively with explosive action for a short amount of time, and whether or not they will be able to subdue the bear with this action before they tire out is key. Assuming this giant polar bear is healthy & not overweight (but simply an enormous bear), it will have the size & strength to prevail more times than not against the attacking lions. Edge to polar bear.
Male Grizzly Bear 500KG VS 2 Male Lions of 200KG: Grizzly bears are probably the most formidable of bears (pound-for-pound) due to their power & aggression. Their claws can reach 10cm in length, and a paw swipe from one is a potent weapon. Lions are fantastic predators that routinely tackle large prey items (Cape buffalo, eland, zebra, wildebeest, etc.), but the females do most of the hunting and will have better teamwork than the males in a confrontation like this. The only reasonable way for the lions to succeed here is to secure a throat bite, but it will be difficult for them to penetrate the grizzly bear's defenses (bites & paw swipes) without being injured in the process. Lions don't encounter bears in the wild, but are capable of overcoming larger animals using a numbers advantage. A pair of 200kg lions will have a good chance of subduing a 500kg Cape buffalo (because they can neutralize the horns with the right positioning), but a bear's weaponry (jaws, controlling forelimbs, & swiping paws) and flexibility (which is better than a bovid's) poses a different type of challenge that increases the difficulty level. Because bears have amazing stamina, one will continue to battle strongly after the lions succumb to fatigue. The 2 lions can certainly pull this off, but the grizzly bear's advantages in size, strength, durability, & endurance will be enough to favor it more times than not. Edge to grizzly bear.
Male Kodiak Bear 850KG VS 5 Female Lioness each 140KG: This will be an enormous Kodiak bear, and assuming its elevated weight isn't due to overeating or lethargy, it will be a very formidable opponent for the lionesses. Bears have great strength, durability, endurance, and weaponry (controlling forelimbs, swiping paws, strong jaws). Lionesses have the typical big cat assets (speed, agility, athleticism, jaws & claws, finishing know-how), and work well as a team when hunting large prey. Lions don't encounter bears in the wild, and as described in the previous answer, a large bear like a Kodiak will offer a unique challenge to a group of lionesses. The lionesses will have difficulty securing a throat bite on an animal that fights back more effectively than anything they're used to encountering, and their window of opportunity will be small considering the advantage in stamina the Kodiak will enjoy. A single swipe from the bear's paw can stun or disable a lioness, but a cautious & well-coordinated attack will give the lionesses a chance to succeed. More than 5 lionesses (or a smaller bear) will likely be needed to enable the cats to obtain victory more consistently. Edge to Kodiak bear.