Alligators Regrow Tails After Amputation, New Study Finds

American alligators fight near launch pad 39A at Kennedy Space Center in Cape Canaveral, Florida June 7, 2007. REUTERS/Charles W. Luzier (UNITED STATES) - RTR1QK2L (REUTERS/Charles W. Luzier)
American alligators fight near launch pad 39A at Kennedy Space Center in Cape Canaveral, Florida June 7, 2007. REUTERS/Charles W. Luzier (UNITED STATES) - RTR1QK2L (REUTERS/Charles W. Luzier)
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Alligators Regrow Tails After Amputation, New Study Finds

American alligators fight near launch pad 39A at Kennedy Space Center in Cape Canaveral, Florida June 7, 2007. REUTERS/Charles W. Luzier (UNITED STATES) - RTR1QK2L (REUTERS/Charles W. Luzier)
American alligators fight near launch pad 39A at Kennedy Space Center in Cape Canaveral, Florida June 7, 2007. REUTERS/Charles W. Luzier (UNITED STATES) - RTR1QK2L (REUTERS/Charles W. Luzier)

Cornered by a dangerous predator, a gecko can self-amputate its still twitching tail, creating a fleeting moment of distraction - a chance for the lizard to flee with its life.

Small reptiles such as geckos and skinks are well known for this remarkable ability to sacrifice their tails. Now, scientists discovered that much larger alligators can regrow theirs too, but only while they're young.

Researchers from the University of Arizona found that Juvenile American alligators (Alligator mississippiensis) can regrow up to 18 percent of their total body length back (about 23 cm or 9 inches of length). By imaging and dissecting the tail regrowth, researchers found alligators do this quite differently from the other animals we know that can regenerate their appendages. The study was published in the latest issue of the journal Scientific Reports.

While other animals self-amputate themselves, small geckos often lose their tails due to injuries caused by dangerous predators or hunting attempts by humans. In addition to difference in amputation conditions, the researchers observed differences in the mechanism and timing of regrowth.

"If injured, reptiles can reform a segmented skeleton, complete with muscles, while the regrown alligator tail is supported by an unsegmented cartilage tube rather than bone," ASU cellular biologist and first author of the research Cindy Xu said in a report published Saturday on the Science Alert website.

"It also may take them considerably longer to regrow their missing bits. While skinks can do it in as little as six months, a related crocodilian takes up to 18 months to reform their tails," she explained.

The researchers reached these conclusions by studying the final regrowth results of American alligators. But given that they are a threatened species, further studies on how this process works may be challenging, but could provide some useful information.

"If we understand how different animals are able to repair and regenerate tissues, this knowledge can then be leveraged to develop medical therapies," said ASU anatomist and co-author Rebecca Fisher.



Water Levels Plummet at Drought-Hit Iraqi Reservoir

Kochar Jamal Tawfeeq, director of the Dukan Dam facility, gives an interview by the reservoir northwest of Iraq's northeastern city of Sulaimaniyah in the autonomous Kurdistan region on June 4, 2025, where waters have been receding due to a mix of factors including lower rainfall, severe drought, and diversion of inflowing rivers from Iran. (AFP)
Kochar Jamal Tawfeeq, director of the Dukan Dam facility, gives an interview by the reservoir northwest of Iraq's northeastern city of Sulaimaniyah in the autonomous Kurdistan region on June 4, 2025, where waters have been receding due to a mix of factors including lower rainfall, severe drought, and diversion of inflowing rivers from Iran. (AFP)
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Water Levels Plummet at Drought-Hit Iraqi Reservoir

Kochar Jamal Tawfeeq, director of the Dukan Dam facility, gives an interview by the reservoir northwest of Iraq's northeastern city of Sulaimaniyah in the autonomous Kurdistan region on June 4, 2025, where waters have been receding due to a mix of factors including lower rainfall, severe drought, and diversion of inflowing rivers from Iran. (AFP)
Kochar Jamal Tawfeeq, director of the Dukan Dam facility, gives an interview by the reservoir northwest of Iraq's northeastern city of Sulaimaniyah in the autonomous Kurdistan region on June 4, 2025, where waters have been receding due to a mix of factors including lower rainfall, severe drought, and diversion of inflowing rivers from Iran. (AFP)

Water levels at Iraq's vast Dukan Dam reservoir have plummeted as a result of dwindling rains and further damming upstream, hitting millions of inhabitants already impacted by drought with stricter water rationing.

Amid these conditions, visible cracks have emerged in the retreating shoreline of the artificial lake, which lies in northern Iraq's autonomous Kurdistan region and was created in the 1950s.

Dukan Lake has been left three quarters empty, with its director Kochar Jamal Tawfeeq explaining its reserves currently stand at around 1.6 billion cubic meters of water out of a possible seven billion.

That is "about 24 percent" of its capacity, the official said, adding that the level of water in the lake had not been so low in roughly 20 years.

Satellite imagery analyzed by AFP shows the lake's surface area shrank by 56 percent between the end of May 2019, the last year it was completely full, and the beginning of June 2025.

Tawfeeq blamed climate change and a "shortage of rainfall" explaining that the timing of the rains had also become irregular.

Over the winter season, Tawfeeq said the Dukan region received 220 millimeters (8.7 inches) of rain, compared to a typical 600 millimeters.

- 'Harvest failed' -

Upstream damming of the Little Zab River, which flows through Iran and feeds Dukan, was a secondary cause of the falling water levels, Tawfeeq explained.

Also buffeted by drought, Iran has built dozens of structures on the river to increase its own water reserves.

Baghdad has criticized these kinds of dams, built both by Iran and neighboring Türkiye, accusing them of significantly restricting water flow into Iraq via the Tigris and Euphrates rivers.

Iraq, and its 46 million inhabitants, have been intensely impacted by the effects of climate change, experiencing rising temperatures, year-on-year droughts and rampant desertification.

At the end of May, the country's total water reserves were at their lowest level in 80 years.

On the slopes above Dukan lies the village of Sarsian, where Hussein Khader Sheikhah, 57, was planting a summer crop on a hectare of land.

The farmer said he hoped a short-term summer crop of the kind typically planted in the area for an autumn harvest -- cucumbers, melons, chickpeas, sunflower seeds and beans -- would help him offset some of the losses over the winter caused by drought.

In winter, in another area near the village, he planted 13 hectares mainly of wheat.

"The harvest failed because of the lack of rain," he explained, adding that he lost an equivalent of almost $5,700 to the poor yield.

"I can't make up for the loss of 13 hectares with just one hectare near the river," he added.

- 'Stricter rationing' -

The water shortage at Dukan has affected around four million people downstream in the neighboring Sulaimaniyah and Kirkuk governorates, including their access to drinking water.

For more than a month, water treatment plants in Kirkuk have been trying to mitigate a sudden, 40 percent drop in the supplies reaching them, according to local water resource official Zaki Karim.

In a country ravaged by decades of conflict, with crumbling infrastructure and floundering public policies, residents already receive water intermittently.

The latest shortages are forcing even "stricter rationing" and more infrequent water distributions, Karim said.

In addition to going door-to-door to raise awareness about water waste, the authorities were also cracking down on illegal access to the water network.

In the province of roughly two million inhabitants, the aim is to minimize the impact on the provincial capital of Kirkuk.

"If some treatment plants experience supply difficulties, we will ensure that there are no total interruptions, so everyone can receive their share," Karim said.