Sunday, July 26, 2026
36.6 C
New Delhi

These fish are born female & later become male; fishing may be changing them at molecular level

These fish are born female and later become male; heavy fishing may be changing them at the molecular level

Pearly razorfish begin life as females before some naturally transition into males.- National Geographic photo

Fishing is known to reduce fish populations and change the size and age of fish found in the wild. But a new study suggests that the effects may go much beyond.Researchers have found that heavy fishing may be changing the biology of the pearly razorfish at the molecular level. The study says intense fishing pressure is linked with changes that may affect how the fish’s genes work.The findings, published in the journal Philosophical Transactions of the Royal Society B, Science X reported, offer some of the first evidence that fishing could influence epigenetic changes.

The pearly razorfish

The pearly razorfish (Xyrichtys novacula) is a small marine fish that lives in sandy coastal waters. It feeds on small sea animals such as shrimp and other tiny creatures found in the seabed.

CJP Jantar Mantar Protest Updates

According to National Geographic, every pearly razorfish is born female. As it grows, some naturally change into males. The dominant male defends a territory shared with several females, helping maintain order in the group and reducing early sex changes among younger females.In Spain’s Balearic Islands, the fish is locally known as raor. It is considered a popular seafood. Every year, many local fishers and families take part in the fishing season to catch it. Because of its popularity, the species experiences heavy fishing pressure in some areas. Scientists wanted to find out whether this pressure affects the fish in ways that go beyond reducing its numbers.

Protected vs fished areas

To study this, researchers collected 120 pearly razorfish from three different regions in the Balearic Islands. Each region included two types of locations.In the first area, fishing is allowed and the fish are regularly caught. The second area is a protected marine reserve where fishing is restricted.Scientists collected small fin samples from the fish and examined the DNA and the epigenetics in the lab.

Locally known as <em>raor</em>, the pearly razorfish is a favourite seafood in Spain’s Balearic Islands.​” msid=”132640935″ width=”” title=”Locally known as raor, the pearly razorfish is a favourite seafood in Spain’s Balearic Islands.​” placeholdersrc=”https://static.toiimg.com/photo/83033472.cms” imgsize=”” resizemode=”4″ offsetvertical=”0″ placeholdermsid=”47529300″ type=”thumb” src=”https://static.toiimg.com/photo/83033472.cms” class=”” data-src=”https://static.toiimg.com/photo/msid-132640935/locally-known-as-emraorem-the-pearly-razorfish-is-a-favourite-seafood-in-spains-balearic-islands.jpg” data-api-prerender=”true”/> </p>
<p> Locally known as raor, the pearly razorfish is a favourite seafood in Spain’s Balearic Islands.​</p>
</p></div>
</p></div>
<p><h2> DNA vs Epigenetics</h2>
</p>
<p> DNA contains genetic information that is passed from one generation to the next. Epigenetics, meanwhile, adds small chemical marks that can control how active certain genes are. These marks act like switches that can turn genes on or off or change how strongly they work.One common type of epigenetic change is DNA methylation. DNA methylation happens when a small chemical group called a methyl group attaches to DNA.This can influence how a gene functions and can sometimes help organisms respond to changes in their environment. </p>
<p><h2> DNA differences</h2>
</p>
<p> When the researchers compared the fish from protected areas with those from heavily fished areas, they found no evidence that the two groups had become genetically different. Meaning, heavy fishing had not changed the actual DNA sequence of the fish.However, the study did find that fish living in heavily fished areas had lower genetic diversity than those inside marine reserves.The researchers also found that the fish living inside protected areas were generally larger and older than fish from places where fishing was common.Although the DNA itself remained largely the same, the researchers discovered important differences in DNA methylation.They identified 291 specific locations in the DNA where these chemical tags differed between fish from protected waters and those from heavily fished areas.According to the researchers, “This represents one of the first lines of evidence demonstrating that fisheries can potentially shape epigenetic variation.”The findings suggest that fishing may be linked with changes in the way genes are regulated, even if the genes themselves remain unchanged. </p>
<p><h2> Fishing not the only reason</h2>
</p>
<p> The researchers said the study found a strong link between fishing pressure and DNA methylation, but it does not prove that fishing directly caused these changes. They suspect that other environmental factors could also be involved.For instance, fish living in heavily fished areas may experience different population densities, food availability, or predator numbers which could influence epigenetic changes.In the study, the DNA methylation patterns remained different even after taking population structure into account. This means that differences in the number or age of fish alone do not fully explain the molecular changes observed in the study.  <a href=Go to Source

Hot this week

Romania shoots down third suspected Russian drone in three days, summons Moscow’s envoy

File photo: Romania detonates Russian drone fragments found near border with Ukraine (Picture credit: Reuters) Romania on Sunday shot down a drone that entered its airspace over the Black Sea, marking the third such interception in a Read More

Slash-and-burn farming was blamed for destroying rainforests, but a study something different

Unwritten social rules, not government oversight, help keep forest land sustainable Slash-and-burn farming was blamed for destroying rainforests, but a study of 18,000 forest patches found community rules can limit clearing and allow Read More

Conservationists filled a 1.2km river channel, new Somerset wetland now attracts rare wildlife

A new waterscape has been created on the Holnicote Estate in Somerset (National Trust photos) Just one year after work completing a river restoration project in south-west England, researchers say the restored landscape has reduced f Read More

Rishikanta Singh Dedicates Historic CWG 2026 Silver To PM Narendra Modi

Show Quick Read Key points generated by AI, verified by newsroom Indian Rishikanta won silver at Commonwealth Games weightlifting event. He broke Games record in snatch, lifting 121kg. Read More

‘Govt-ordered probe an eyewash’: Tripura Congress MLA demands judicial inquiry into DGP Anurag Dhankar’s death

Tripura DGP Anurag Dhankar was found dead in state police headquarters on July 20 NEW DELHI: Tripura Congress MLA Sudip Roy Barman on Sunday reiterated the party’s demand for a judicial probe into the death of state DGP Anurag Read More

Topics

Romania shoots down third suspected Russian drone in three days, summons Moscow’s envoy

File photo: Romania detonates Russian drone fragments found near border with Ukraine (Picture credit: Reuters) Romania on Sunday shot down a drone that entered its airspace over the Black Sea, marking the third such interception in a Read More

Slash-and-burn farming was blamed for destroying rainforests, but a study something different

Unwritten social rules, not government oversight, help keep forest land sustainable Slash-and-burn farming was blamed for destroying rainforests, but a study of 18,000 forest patches found community rules can limit clearing and allow Read More

Conservationists filled a 1.2km river channel, new Somerset wetland now attracts rare wildlife

A new waterscape has been created on the Holnicote Estate in Somerset (National Trust photos) Just one year after work completing a river restoration project in south-west England, researchers say the restored landscape has reduced f Read More

Rishikanta Singh Dedicates Historic CWG 2026 Silver To PM Narendra Modi

Show Quick Read Key points generated by AI, verified by newsroom Indian Rishikanta won silver at Commonwealth Games weightlifting event. He broke Games record in snatch, lifting 121kg. Read More

‘Govt-ordered probe an eyewash’: Tripura Congress MLA demands judicial inquiry into DGP Anurag Dhankar’s death

Tripura DGP Anurag Dhankar was found dead in state police headquarters on July 20 NEW DELHI: Tripura Congress MLA Sudip Roy Barman on Sunday reiterated the party’s demand for a judicial probe into the death of state DGP Anurag Read More

Raveena criticises protests hijacked by hooligans, political parties: ‘Some just wanted to make reels’

While protests at Janter Manter by the Cockroach Janta Party (CJP) against the NEET paper leek, have taken over social media and people are now celebrating Dharmendra Pradhan’s resignation, actress Raveena Tandon has applauded Read More

Vaibhav Sooryavanshi Stars Again As India Post 192/5 Against Zimbabwe

Show Quick Read Key points generated by AI, verified by newsroom India posted 192/5, setting Zimbabwe a 193-run target. Vaibhav Sooryavanshi’s 81 off 49 balls anchored India’s innings. Read More

WATCH: Fan Asks Ishan Kishan To Sign His Bald Head; Hilarious Moment Goes Viral

Show Quick Read Key points generated by AI, verified by newsroom Ishan Kishan signed fan’s bald head, widely shared online. His match-winning 81 runs helped India seal series victory. Read More

Related Articles