Rhea chicks enjoy feathery piggyback rides.Mehgan Murphy/Smithsonian’s National Zoo

Rhea dads, not moms, build the nest and incubate eggs. They even take care of their chicks for six months after they hatch. The lucky chicks benefit from dad's imposing size.

This particular male is 5 feet 8 inches tall. After observing this dad on the job, biologist Sara Hallager at Smithsonian's National Zoo said, "The dad is doing a great job. First-time parents sometimes don't know what to do. With this guy, it's pure instinct."

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Male seahorses are Mr. Mom.Owen Evans, Flickr

Male seahorses take fathering to a whole new level -- pregnancy.

"From a research standpoint, it's interesting because there aren't very many species in which there is a sex role reversal," Adam Jones of Texas A&M University said. "It provides a unique opportunity to study sexual selection in this reversed context."

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Adelie penguin fathers babysit for two weeks at a time without a single break.Emma Marks

Adelie penguin dads are the ultimate babysitters. They must tend to eggs for two weeks, without even breaking to eat, while mom returns to sea. As a result it helps if dad is fat to begin with.

"A fat male is a good choice for a female because males do so much of the offspring care," said Dianne Brunton of Massey University, who studied the penguins in Antarctica. "They're able to incubate the eggs for longer and use up their fat stores, while skinny males aren't able to do that."

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Burying beetle dads put up with begging, barfing and prodding.University of Exeter

It's a wonder that male burying beetles become fathers at all. According to Megan Head of the University of Exeter, burying beetle dads must attend to offspring that beg for food and poke at them. As if that isn't bad enough, dad has to respond by regurgitating partially digested food.

Head and her team determined that older dads are more caring than younger ones. Instead of running around, trying to find new love interests, the more senior dads tended to settle down and devote greater time to parental care.

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A sand goby dad is a true fan of its family.Wikimedia Commons

Sand goby dads must end every day feeling tired. They first have to find mussels and other shells for their families to hide under. They defend these shells, hollowing out space under them and piling sand on top to disguise the shells from predators.

As if the guarding work weren't enough, the dads then use their pectoral fins to fan water over eggs. This creates a current of fresh, oxygenated water needed for the eggs -- and their precious contents -- to mature.

One upside is that females find all of this very attractive. As Sigal Balshine of McMaster University, who studied the fish, said: "Being a good father is very sexy. This is almost a cliché, as it has become a standard joke that the best way to get women to be interested in you as a single guy is to borrow a baby or a puppy. Women obviously find 'caring guys' very sexy."

Meerkat fathers patiently teach their kids what's right and wrong.Wikimedia Commons

School is often in session for young meerkats, with the top lesson being how to obtain food. Dads, as well as moms and even older considerate helpers, watch after youths, teaching them valuable skills without putting them in harm's way. How can a lesson on hunting, though, not be dangerous?

To solve that problem, dad or another instructor incrementally introduces dead, injured and then finally live prey to pups, according to Alex Thornton of the University of Cambridge and his team.

Like any good teacher, dad or the helpers also monitor the pup. If pups are reluctant to handle prey, dad nudges the item towards them to encourage interaction. Additionally, when the prey wanders off, dad retrieves it and returns it to his pup, sometimes further disabling it to make sure that it's safe for his pup to handle and eat.

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In trouble? If you're a baby baboon, dad will come to your rescue.Wikimedia Commons

Male baboons tend to be big and ornery, but they are devoted to their offspring and will risk their lives to get them out of a jam.

All baby baboons might look alike to untrained human eyes, but Duke University researcher Susan Alberts and colleagues found that dads time and again give preferential treatment to their own genetic offspring.

"If male baboons care for their kids -- and baboons are almost among the least likely societies where you would expect to see this -- then it suggests that paternal care has really deep evolutionary roots in primates," Alberts said.

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Single dad spiders care for hundreds of eggs.Gustavo Requena

Single fatherhood is a challenge many arachnids undertake, guarding eggs laid by females despite the costs to their own health and mating benefits.

The male harvestman spider in this image carefully tends to the egg clutch. As for sand gobies, such care has an added perk: female spiders often find caring dads to be very sexy. Note the female at the top of the leaf, who is likely checking out this dutiful dad.

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Fossils suggest some dinosaurs were first-rate dads.Mick Ellison, American Museum of Natural History

Fossils provide convincing evidence that at least some dinosaurs were caring fathers. This drawing depicts the dinosaur Citipati on a nest that was found in the Gobi desert of Mongolia by the American Museum of Natural History.

"In those cases where adult dinosaurs have been found on top of nests, we found that the volume or mass of the egg clutch (total number of eggs in the nest) is very large relative to the size of the nesting animals," Gregory Erickson of Florida State University said. "This suggests multiple females contributed the eggs and the male guarded them. Notably, the ratio of egg volumes to the nesting animal's size is consistent with those in living birds where the male is the sole or primary nest attendant."

He and his colleagues think that this protective behavior passed down to certain bird species, particularly emus and other ground-dwelling birds, which tend to have doting dads.

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You are what your dad eats, so caring dads care about what they consume.Rabble, Flickr

As we know, human dads area, on average, pretty stand-up parents.

One of the best things a human dad can do is to eat healthy foods during the year he plans to sire children, and ideally before that too. Oliver Rando of the University of Massachusetts Medical School and his team found that the diets of males, and not just females, affected the health of their future offspring. What's more, the effect could carry over to their grandchildren.

Other research has found that fathers on high fat diets can pass health problems on to their children. The best human dads therefore not only take care of their kids, but they also take good care of themselves.