Although it is not officially recorded as extinct, no one __________ (seen) a Yangtze River Dolphin since 2002.
Although it is not officially recorded as extinct, no one HAS SEEN a Yangtze River Dolphin since 2002.
It is believed that Javan Tigers became extinct soon after Caspian Tigers __________ (disappear).
It is believed that Javan Tigers became extinct soon after Caspian Tigers HAD DISAPPEARED.
Scientists confirm that Polar Bears __________ (become) extinct by 2050.
Scientists confirm that Polar Bears WILL HAVE BECOME extinct by 2050.
The IUCN officially __________ (declare) the Spix Macaw extinct in the wild in 2019.
The IUCN officially DECLARED the Spix Macaw extinct in the wild in 2019.
Considered the first direct victim of climate change, the Golden Toads __________ (abandon) their eggs as the pools in the forest were drying up.
Considered the first direct victim of climate change, the Golden Toads WERE ABANDONING their eggs as the pools in the forest were drying up.
Leatherback Turtles, the largest sea turtle species, __________ (list) as an endangered species since 1970.
Leatherback Turtles, the largest sea turtle species, HAVE BEEN LISTED as an endangered species since 1970.
Environmentalists __________ (warn) us constantly for several years before the Pyrenean Ibex became extinct in Spain.
Environmentalists HAD BEEN WARNING us constantly for several years before the Pyrenean Ibex became extinct in Spain.
Currently, there are about 20,000 white rhinos is Africa. Studies show they __________ (vanish) in a hundred years' time.
Currently, there are about 20,000 white rhinos is Africa. Studies show they WILL HAVE VANISHED in a hundred years' time.
Handfish were an unusual group of species whose front fins looked somewhat like human appendages, which they __________ (use) walk around the ocean floor.
Handfish were an unusual group of species whose front fins looked somewhat like human appendages, which they USED TO walk around the ocean floor.
The ivory-billed woodpecker is one of 22 species of birds, fish, mussels, and bats (and one species of plant) that __________ (be declared) extinct in the US in 2021
The ivory-billed woodpecker is one of 22 species of birds, fish, mussels, and bats (and one species of plant) that WERE DECLARED extinct in the US in 2021
