The Bronx Zoo got two new additions this spring: a pair of baby gorillas. One was born on March 10, the other on April 17. Though they have two different mothers, Julia and Tuti, they share the same father, Ernie. Zookeepers haven’t determined the sex of the two babies yet because they have not been able to get close enough to examine them, the New York Daily News reports.
Newborn gorillas weight between 4 and 5 pounds, though they will grow to be between 350 and 450 pounds if male or 150 to 250 pounds if female.
The babies are the first newcomers to the zoo’s Congo Gorilla Forest in eight years. Western lowland gorillas, native to equatorial Africa, are critically endangered.
More Must-Reads from TIME
- Donald Trump Is TIME's 2024 Person of the Year
- Why We Chose Trump as Person of the Year
- Is Intermittent Fasting Good or Bad for You?
- The 100 Must-Read Books of 2024
- The 20 Best Christmas TV Episodes
- Column: If Optimism Feels Ridiculous Now, Try Hope
- The Future of Climate Action Is Trade Policy
- Merle Bombardieri Is Helping People Make the Baby Decision
Write to Eliana Dockterman at eliana.dockterman@time.com