The five baby gorillas born in 2014 and 2015 at the Bronx Zoo can now be seen at the zoo's Congo Gorilla Forest.

The Wildlife Conservation Society announced that the toddlers—Mjukuu and Lincoln are two years old; Kamara, Mokonzi, and Kidogo Njemba are the one-year-olds—were joining the exhibit last Thursday: "Their playful interactions with their parents and one another give zoo visitors an opportunity to observe the family dynamics and see how their personalities have developed." All five of the little ones were sired by Ernie, a silverback male.

They are all pretty adorable:

The WCS notes that the "Bronx Zoo has a successful history breeding gorillas as part of the Species Survival Plan, a cooperative breeding program designed to enhance the genetic viability of animal populations in zoos accredited by the Association of Zoos and Aquariums. The Congo Gorilla Forest home to one of the largest groups of gorillas in North America. There are two breeding troops along with a troop of young males. This award-winning habitat has raised more than $12 million for WCS’s conservation programs in Africa through admission fees."

Last Saturday, a 17-year-old silverback gorilla named Harambe was killed when a three-year-old boy fell into the Cincinnati Zoo's gorilla exhibit. The boy's mother was reportedly distracted by her other children and didn't realize that her son had climbed over the railing, across about four feet of ground and then fell over 10 feet into the main exhibit. Zoo officials explained that they decided to fatally shoot Harambe, because it wasn't clear that tranquilizers would immediately calm the critically endangered 450-pound animal.

Kim O'Connor, a witness who filmed some of the incident, said she didn't capture the whole thing, "What you don't see is the way he pulled the boy up the wall. He was treating the little boy like a Raggedy Ann doll in his grip."

The boy suffered a concussion and minor injuries. His family said in a statement, "We are so thankful to the Lord that our child is safe. He is home and doing just fine… We know that this was a very difficult decision for them, and that they are grieving the loss of their gorilla." They urged people to donate to the Cincinnati Zoo.

The incident prompted widespread outrage and empathy—over parenting, the zoo's decision, etc.—as well as scrutiny over zoo exhibits. Primatologist Frans de Waal admitted he couldn't decide whether the zoo's actions were right or wrong, noting it was a "horrible dilemma." A contributor to the NY Times' Dot Earth blog shared an intimate photo taken by his son at the Bronx Zoo's Congo Gorilla Forest ("The exhibit was powerful and memorable; my wife and I are still haunted by our eye contact with such a close hominid relation.")—and wondered if zoos are appropriate places for gorillas.

Zoo designers are now looking at whether their designs are enough. From NBC New York:

Today's designs leave 4 feet between a railing and a moat so that anyone falling from the railing will not land in the moat. Railings themselves sometimes have uneven pickets to make it difficult for anyone to sit on top of them.

"That 4-foot space, that’s come about over time because there have been so many incidents of parents setting a child on the railing," said Patrick Janikowski, a principal of PJA Architects and Landscape Architects, a Seattle-based firm specializing in zoo design.

"I don't want to say it’s designed for stupidity, but that's the reason that that is designed that way, as a secondary precaution against falling into the moat," he said.

"All AZA-accredited zoos and aquariums are required to conduct four emergency drills per year, as well as have emergency procedures prepared for dangerous animals, like gorillas," Rob Vernon, spokesman for the Association of Zoos and Aquariums, told us. "That preparation by Cincinnati Zoo led to prompt resolution of the incident last Saturday. Incidents like this are very rare, and zoos remain very safe places for families to visit."