English Comprehension PYQs

**Direction: Read the given passage carefully to answer the following questions.

Each question will have five alternatives as its answer. Choose the correct option as your answer.**

Trade and investment Ministers of the G-20 nations, representing 80% of the world economy’s output, three-quarters of trade flows and three-fifths of the population, concluded their deliberations under India’s presidency of the bloc last week. A comprehensive communiqué was scuttled as China and Russia blocked a reference to geopolitical issues arising from the conflict in Ukraine, as has been the case since last year’s G-20 Bali summit. Yet, amid flailing prospects for global trade and investment in the near-term, the G-20 nations did agree to take joint actions to reaffirm the world’s faith in cross-border commerce and investment flows as a route to prosperity and growth for all. The government counted five concrete and action-oriented deliverables from the meet, including a dialogue on global standards to bridge regulatory divergences across countries and a compendium on best practices for mutual recognition of qualifications for professional services such as medicine, law and nursing. Asserting that the trade track outcomes were the most significant so far in the G-20 parleys, Commerce and Industry Minister Piyush Goyal highlighted the other three deliverables as new elements that hold importance for India. A generic framework to map global value chains, essentially to identify the weakest links and mitigate any shocks like those seen during the pandemic, is a good idea that may prove tricky to execute. Digitalisation of trade documents to ease flow of goods and services is welcome, but the principles identified in the pact pertain to paperwork on transactions such as transport, insurance, and storage, “not necessarily” to government filings for cross-border trade.

What has been coined as the Jaipur Call for Action to enhance Micro, Small and Medium Enterprises’ (MSMEs’) access to information’ may yield quicker and more tangible results. The International Trade Centre, WTO and UNCTAD, which operate the Global Trade Helpdesk, have been urged to work with G-20 members to upgrade their data portal for businesses and bridge the “information asymmetry” that often hinders small players. This resonates with Prime Minister Narendra Modi’s plea that G-20 Ministers strive to help MSMEs which account for 60%-70% of employment and 50% of the global GDP, integrate with global value chains as empowering them translates to societal empowerment. India, on its part, must also consider steps to bolster the capacity of its small enterprises. For one, its nudge for greenfield investments through productivity-linked incentives across sectors, can be tweaked to create a separate window for fresh outlays by MSMEs that cannot qualify for incentives based on larger investments. Moreover, bureaucratic red tape may have turned into a ‘red carpet’ for some large investors, but for smaller firms, getting a project off the ground is not easy yet.

Read the given passage carefully and answer the following question.

In 1984, researchers spotted dolphins doing something broken in Shark Bay, Western Australia. When the animals got hungry, they ripped a marine basket sponge from the sea floor and fitted it over their beaks like a person would fit a glove in a hand. The scientists suspected that as the dolphins foraged for fish, the sponges protected their beaks, or rostra, from the rocks and acoustic chunks of coral that litter the sea floor, making this behaviour the first example of tool use in this species.

The researchers surmised that a long time ago one ingenious Shark Bay dolphin figured out that by prodding the sediments with a sponge attached to her beak, she could stir up these swim bladder-less fish without being hurt. Eventually, such a technique became apparent among other dolphins. But why do dolphins go through all of this trouble when they could simply snag a fish from the open sea? The answer is that the bottom-dwelling fish are a lot more nutritious.

Some species also don't have swim bladders or gas chambers that help other fish control their buoyancy as they travel up and down the water column. In the Bahamas, where dolphins are also known to forage for bottom-dwelling fish, dolphins hunt partly by echolocating these bladders, which give off a strong popular signal. That helps the cetaceans find prey even when it's buried in sea sand. But bottom-dwelling fish, such as Barred Sandperch, which are favoured by some Shark Bay dolphins, don't have swim bladders and so are harder to find with echolocation. The sea floor is not nearly as soft here as it is in the Bahamas, so if dolphins want to probe for these fish, they risk injuring their rostra.

Not every dolphin in Shark Bay hunts with sponges. "It's primarily done by females," says Janet Mann, a behavioural ecologist. She believes the female dolphins invented the method because of the "selective pressures they face while raising a calf as long as they do," about 4 to 5 years. "These clever dolphins have figured out a way to target fish that other dolphins cannot," she says, adding that even the local fishermen do not catch, or even know about, this particular species. Mann's previous research has shown that dolphin mothers pass the sponging method to their daughters and some of their sons, rare evidence of a cultural tradition in an animal other than humans. The team has documented three generations of sponging dolphins.

The foraging technique came to light a few decades ago - very recently in evolutionary terms - when a local fisherman spotted what looked like a strange tumour on a dolphin’s nose. Researchers eventually worked out that the ‘tumour’ was a conically shaped sponge and it became unusual that the dolphins would spend considerable time searching for one the right shape to fit their nose. The sponge is used to scatter the sand gently on the sea floor and disturb buried fish. When a fish is spotted, the dolphin drops the sponge and gives chase. "It has been thought that behaviours which are exclusively learnt from one parent are not very stable. With our model we could now show that sponging can be a stable behaviour," said Dr Anna Kopps, a biologist at the University of New South Wales.

Read the given passage carefully and answer the following question.

In 1984, researchers spotted dolphins doing something broken in Shark Bay, Western Australia. When the animals got hungry, they ripped a marine basket sponge from the sea floor and fitted it over their beaks like a person would fit a glove in a hand. The scientists suspected that as the dolphins foraged for fish, the sponges protected their beaks, or rostra, from the rocks and acoustic chunks of coral that litter the sea floor, making this behaviour the first example of tool use in this species.

The researchers surmised that a long time ago one ingenious Shark Bay dolphin figured out that by prodding the sediments with a sponge attached to her beak, she could stir up these swim bladder-less fish without being hurt. Eventually, such a technique became apparent among other dolphins. But why do dolphins go through all of this trouble when they could simply snag a fish from the open sea? The answer is that the bottom-dwelling fish are a lot more nutritious.

Some species also don't have swim bladders or gas chambers that help other fish control their buoyancy as they travel up and down the water column. In the Bahamas, where dolphins are also known to forage for bottom-dwelling fish, dolphins hunt partly by echolocating these bladders, which give off a strong popular signal. That helps the cetaceans find prey even when it's buried in sea sand. But bottom-dwelling fish, such as Barred Sandperch, which are favoured by some Shark Bay dolphins, don't have swim bladders and so are harder to find with echolocation. The sea floor is not nearly as soft here as it is in the Bahamas, so if dolphins want to probe for these fish, they risk injuring their rostra.

Not every dolphin in Shark Bay hunts with sponges. "It's primarily done by females," says Janet Mann, a behavioural ecologist. She believes the female dolphins invented the method because of the "selective pressures they face while raising a calf as long as they do," about 4 to 5 years. "These clever dolphins have figured out a way to target fish that other dolphins cannot," she says, adding that even the local fishermen do not catch, or even know about, this particular species. Mann's previous research has shown that dolphin mothers pass the sponging method to their daughters and some of their sons, rare evidence of a cultural tradition in an animal other than humans. The team has documented three generations of sponging dolphins.

The foraging technique came to light a few decades ago - very recently in evolutionary terms - when a local fisherman spotted what looked like a strange tumour on a dolphin’s nose. Researchers eventually worked out that the ‘tumour’ was a conically shaped sponge and it became unusual that the dolphins would spend considerable time searching for one the right shape to fit their nose. The sponge is used to scatter the sand gently on the sea floor and disturb buried fish. When a fish is spotted, the dolphin drops the sponge and gives chase. "It has been thought that behaviours which are exclusively learnt from one parent are not very stable. With our model we could now show that sponging can be a stable behaviour," said Dr Anna Kopps, a biologist at the University of New South Wales.

Read the given passage carefully and answer the following question.

In 1984, researchers spotted dolphins doing something broken in Shark Bay, Western Australia. When the animals got hungry, they ripped a marine basket sponge from the sea floor and fitted it over their beaks like a person would fit a glove in a hand. The scientists suspected that as the dolphins foraged for fish, the sponges protected their beaks, or rostra, from the rocks and acoustic chunks of coral that litter the sea floor, making this behaviour the first example of tool use in this species.

The researchers surmised that a long time ago one ingenious Shark Bay dolphin figured out that by prodding the sediments with a sponge attached to her beak, she could stir up these swim bladder-less fish without being hurt. Eventually, such a technique became apparent among other dolphins. But why do dolphins go through all of this trouble when they could simply snag a fish from the open sea? The answer is that the bottom-dwelling fish are a lot more nutritious.

Some species also don't have swim bladders or gas chambers that help other fish control their buoyancy as they travel up and down the water column. In the Bahamas, where dolphins are also known to forage for bottom-dwelling fish, dolphins hunt partly by echolocating these bladders, which give off a strong popular signal. That helps the cetaceans find prey even when it's buried in sea sand. But bottom-dwelling fish, such as Barred Sandperch, which are favoured by some Shark Bay dolphins, don't have swim bladders and so are harder to find with echolocation. The sea floor is not nearly as soft here as it is in the Bahamas, so if dolphins want to probe for these fish, they risk injuring their rostra.

Not every dolphin in Shark Bay hunts with sponges. "It's primarily done by females," says Janet Mann, a behavioural ecologist. She believes the female dolphins invented the method because of the "selective pressures they face while raising a calf as long as they do," about 4 to 5 years. "These clever dolphins have figured out a way to target fish that other dolphins cannot," she says, adding that even the local fishermen do not catch, or even know about, this particular species. Mann's previous research has shown that dolphin mothers pass the sponging method to their daughters and some of their sons, rare evidence of a cultural tradition in an animal other than humans. The team has documented three generations of sponging dolphins.

The foraging technique came to light a few decades ago - very recently in evolutionary terms - when a local fisherman spotted what looked like a strange tumour on a dolphin’s nose. Researchers eventually worked out that the ‘tumour’ was a conically shaped sponge and it became unusual that the dolphins would spend considerable time searching for one the right shape to fit their nose. The sponge is used to scatter the sand gently on the sea floor and disturb buried fish. When a fish is spotted, the dolphin drops the sponge and gives chase. "It has been thought that behaviours which are exclusively learnt from one parent are not very stable. With our model we could now show that sponging can be a stable behaviour," said Dr Anna Kopps, a biologist at the University of New South Wales.

Read the given passage carefully and answer the following question.

In 1984, researchers spotted dolphins doing something broken in Shark Bay, Western Australia. When the animals got hungry, they ripped a marine basket sponge from the sea floor and fitted it over their beaks like a person would fit a glove in a hand. The scientists suspected that as the dolphins foraged for fish, the sponges protected their beaks, or rostra, from the rocks and acoustic chunks of coral that litter the sea floor, making this behaviour the first example of tool use in this species.

The researchers surmised that a long time ago one ingenious Shark Bay dolphin figured out that by prodding the sediments with a sponge attached to her beak, she could stir up these swim bladder-less fish without being hurt. Eventually, such a technique became apparent among other dolphins. But why do dolphins go through all of this trouble when they could simply snag a fish from the open sea? The answer is that the bottom-dwelling fish are a lot more nutritious.

Some species also don't have swim bladders or gas chambers that help other fish control their buoyancy as they travel up and down the water column. In the Bahamas, where dolphins are also known to forage for bottom-dwelling fish, dolphins hunt partly by echolocating these bladders, which give off a strong popular signal. That helps the cetaceans find prey even when it's buried in sea sand. But bottom-dwelling fish, such as Barred Sandperch, which are favoured by some Shark Bay dolphins, don't have swim bladders and so are harder to find with echolocation. The sea floor is not nearly as soft here as it is in the Bahamas, so if dolphins want to probe for these fish, they risk injuring their rostra.

Not every dolphin in Shark Bay hunts with sponges. "It's primarily done by females," says Janet Mann, a behavioural ecologist. She believes the female dolphins invented the method because of the "selective pressures they face while raising a calf as long as they do," about 4 to 5 years. "These clever dolphins have figured out a way to target fish that other dolphins cannot," she says, adding that even the local fishermen do not catch, or even know about, this particular species. Mann's previous research has shown that dolphin mothers pass the sponging method to their daughters and some of their sons, rare evidence of a cultural tradition in an animal other than humans. The team has documented three generations of sponging dolphins.

The foraging technique came to light a few decades ago - very recently in evolutionary terms - when a local fisherman spotted what looked like a strange tumour on a dolphin’s nose. Researchers eventually worked out that the ‘tumour’ was a conically shaped sponge and it became unusual that the dolphins would spend considerable time searching for one the right shape to fit their nose. The sponge is used to scatter the sand gently on the sea floor and disturb buried fish. When a fish is spotted, the dolphin drops the sponge and gives chase. "It has been thought that behaviours which are exclusively learnt from one parent are not very stable. With our model we could now show that sponging can be a stable behaviour," said Dr Anna Kopps, a biologist at the University of New South Wales.

Read the given passage carefully and answer the following question.

In 1984, researchers spotted dolphins doing something broken in Shark Bay, Western Australia. When the animals got hungry, they ripped a marine basket sponge from the sea floor and fitted it over their beaks like a person would fit a glove in a hand. The scientists suspected that as the dolphins foraged for fish, the sponges protected their beaks, or rostra, from the rocks and acoustic chunks of coral that litter the sea floor, making this behaviour the first example of tool use in this species.

The researchers surmised that a long time ago one ingenious Shark Bay dolphin figured out that by prodding the sediments with a sponge attached to her beak, she could stir up these swim bladder-less fish without being hurt. Eventually, such a technique became apparent among other dolphins. But why do dolphins go through all of this trouble when they could simply snag a fish from the open sea? The answer is that the bottom-dwelling fish are a lot more nutritious.

Some species also don't have swim bladders or gas chambers that help other fish control their buoyancy as they travel up and down the water column. In the Bahamas, where dolphins are also known to forage for bottom-dwelling fish, dolphins hunt partly by echolocating these bladders, which give off a strong popular signal. That helps the cetaceans find prey even when it's buried in sea sand. But bottom-dwelling fish, such as Barred Sandperch, which are favoured by some Shark Bay dolphins, don't have swim bladders and so are harder to find with echolocation. The sea floor is not nearly as soft here as it is in the Bahamas, so if dolphins want to probe for these fish, they risk injuring their rostra.

Not every dolphin in Shark Bay hunts with sponges. "It's primarily done by females," says Janet Mann, a behavioural ecologist. She believes the female dolphins invented the method because of the "selective pressures they face while raising a calf as long as they do," about 4 to 5 years. "These clever dolphins have figured out a way to target fish that other dolphins cannot," she says, adding that even the local fishermen do not catch, or even know about, this particular species. Mann's previous research has shown that dolphin mothers pass the sponging method to their daughters and some of their sons, rare evidence of a cultural tradition in an animal other than humans. The team has documented three generations of sponging dolphins.

The foraging technique came to light a few decades ago - very recently in evolutionary terms - when a local fisherman spotted what looked like a strange tumour on a dolphin’s nose. Researchers eventually worked out that the ‘tumour’ was a conically shaped sponge and it became unusual that the dolphins would spend considerable time searching for one the right shape to fit their nose. The sponge is used to scatter the sand gently on the sea floor and disturb buried fish. When a fish is spotted, the dolphin drops the sponge and gives chase. "It has been thought that behaviours which are exclusively learnt from one parent are not very stable. With our model we could now show that sponging can be a stable behaviour," said Dr Anna Kopps, a biologist at the University of New South Wales.

Read the given passage carefully and answer the following question.

In 1984, researchers spotted dolphins doing something broken in Shark Bay, Western Australia. When the animals got hungry, they ripped a marine basket sponge from the sea floor and fitted it over their beaks like a person would fit a glove in a hand. The scientists suspected that as the dolphins foraged for fish, the sponges protected their beaks, or rostra, from the rocks and acoustic chunks of coral that litter the sea floor, making this behaviour the first example of tool use in this species.

The researchers surmised that a long time ago one ingenious Shark Bay dolphin figured out that by prodding the sediments with a sponge attached to her beak, she could stir up these swim bladder-less fish without being hurt. Eventually, such a technique became apparent among other dolphins. But why do dolphins go through all of this trouble when they could simply snag a fish from the open sea? The answer is that the bottom-dwelling fish are a lot more nutritious.

Some species also don't have swim bladders or gas chambers that help other fish control their buoyancy as they travel up and down the water column. In the Bahamas, where dolphins are also known to forage for bottom-dwelling fish, dolphins hunt partly by echolocating these bladders, which give off a strong popular signal. That helps the cetaceans find prey even when it's buried in sea sand. But bottom-dwelling fish, such as Barred Sandperch, which are favoured by some Shark Bay dolphins, don't have swim bladders and so are harder to find with echolocation. The sea floor is not nearly as soft here as it is in the Bahamas, so if dolphins want to probe for these fish, they risk injuring their rostra.

Not every dolphin in Shark Bay hunts with sponges. "It's primarily done by females," says Janet Mann, a behavioural ecologist. She believes the female dolphins invented the method because of the "selective pressures they face while raising a calf as long as they do," about 4 to 5 years. "These clever dolphins have figured out a way to target fish that other dolphins cannot," she says, adding that even the local fishermen do not catch, or even know about, this particular species. Mann's previous research has shown that dolphin mothers pass the sponging method to their daughters and some of their sons, rare evidence of a cultural tradition in an animal other than humans. The team has documented three generations of sponging dolphins.

The foraging technique came to light a few decades ago - very recently in evolutionary terms - when a local fisherman spotted what looked like a strange tumour on a dolphin’s nose. Researchers eventually worked out that the ‘tumour’ was a conically shaped sponge and it became unusual that the dolphins would spend considerable time searching for one the right shape to fit their nose. The sponge is used to scatter the sand gently on the sea floor and disturb buried fish. When a fish is spotted, the dolphin drops the sponge and gives chase. "It has been thought that behaviours which are exclusively learnt from one parent are not very stable. With our model we could now show that sponging can be a stable behaviour," said Dr Anna Kopps, a biologist at the University of New South Wales.

Read the given passage carefully and answer the following question.

In 1984, researchers spotted dolphins doing something broken in Shark Bay, Western Australia. When the animals got hungry, they ripped a marine basket sponge from the sea floor and fitted it over their beaks like a person would fit a glove in a hand. The scientists suspected that as the dolphins foraged for fish, the sponges protected their beaks, or rostra, from the rocks and acoustic chunks of coral that litter the sea floor, making this behaviour the first example of tool use in this species.

The researchers surmised that a long time ago one ingenious Shark Bay dolphin figured out that by prodding the sediments with a sponge attached to her beak, she could stir up these swim bladder-less fish without being hurt. Eventually, such a technique became apparent among other dolphins. But why do dolphins go through all of this trouble when they could simply snag a fish from the open sea? The answer is that the bottom-dwelling fish are a lot more nutritious.

Some species also don't have swim bladders or gas chambers that help other fish control their buoyancy as they travel up and down the water column. In the Bahamas, where dolphins are also known to forage for bottom-dwelling fish, dolphins hunt partly by echolocating these bladders, which give off a strong popular signal. That helps the cetaceans find prey even when it's buried in sea sand. But bottom-dwelling fish, such as Barred Sandperch, which are favoured by some Shark Bay dolphins, don't have swim bladders and so are harder to find with echolocation. The sea floor is not nearly as soft here as it is in the Bahamas, so if dolphins want to probe for these fish, they risk injuring their rostra.

Not every dolphin in Shark Bay hunts with sponges. "It's primarily done by females," says Janet Mann, a behavioural ecologist. She believes the female dolphins invented the method because of the "selective pressures they face while raising a calf as long as they do," about 4 to 5 years. "These clever dolphins have figured out a way to target fish that other dolphins cannot," she says, adding that even the local fishermen do not catch, or even know about, this particular species. Mann's previous research has shown that dolphin mothers pass the sponging method to their daughters and some of their sons, rare evidence of a cultural tradition in an animal other than humans. The team has documented three generations of sponging dolphins.

The foraging technique came to light a few decades ago - very recently in evolutionary terms - when a local fisherman spotted what looked like a strange tumour on a dolphin’s nose. Researchers eventually worked out that the ‘tumour’ was a conically shaped sponge and it became unusual that the dolphins would spend considerable time searching for one the right shape to fit their nose. The sponge is used to scatter the sand gently on the sea floor and disturb buried fish. When a fish is spotted, the dolphin drops the sponge and gives chase. "It has been thought that behaviours which are exclusively learnt from one parent are not very stable. With our model we could now show that sponging can be a stable behaviour," said Dr Anna Kopps, a biologist at the University of New South Wales.

Read the given passage carefully and answer the following question.

In 1984, researchers spotted dolphins doing something broken in Shark Bay, Western Australia. When the animals got hungry, they ripped a marine basket sponge from the sea floor and fitted it over their beaks like a person would fit a glove in a hand. The scientists suspected that as the dolphins foraged for fish, the sponges protected their beaks, or rostra, from the rocks and acoustic chunks of coral that litter the sea floor, making this behaviour the first example of tool use in this species.

The researchers surmised that a long time ago one ingenious Shark Bay dolphin figured out that by prodding the sediments with a sponge attached to her beak, she could stir up these swim bladder-less fish without being hurt. Eventually, such a technique became apparent among other dolphins. But why do dolphins go through all of this trouble when they could simply snag a fish from the open sea? The answer is that the bottom-dwelling fish are a lot more nutritious.

Some species also don't have swim bladders or gas chambers that help other fish control their buoyancy as they travel up and down the water column. In the Bahamas, where dolphins are also known to forage for bottom-dwelling fish, dolphins hunt partly by echolocating these bladders, which give off a strong popular signal. That helps the cetaceans find prey even when it's buried in sea sand. But bottom-dwelling fish, such as Barred Sandperch, which are favoured by some Shark Bay dolphins, don't have swim bladders and so are harder to find with echolocation. The sea floor is not nearly as soft here as it is in the Bahamas, so if dolphins want to probe for these fish, they risk injuring their rostra.

Not every dolphin in Shark Bay hunts with sponges. "It's primarily done by females," says Janet Mann, a behavioural ecologist. She believes the female dolphins invented the method because of the "selective pressures they face while raising a calf as long as they do," about 4 to 5 years. "These clever dolphins have figured out a way to target fish that other dolphins cannot," she says, adding that even the local fishermen do not catch, or even know about, this particular species. Mann's previous research has shown that dolphin mothers pass the sponging method to their daughters and some of their sons, rare evidence of a cultural tradition in an animal other than humans. The team has documented three generations of sponging dolphins.

The foraging technique came to light a few decades ago - very recently in evolutionary terms - when a local fisherman spotted what looked like a strange tumour on a dolphin’s nose. Researchers eventually worked out that the ‘tumour’ was a conically shaped sponge and it became unusual that the dolphins would spend considerable time searching for one the right shape to fit their nose. The sponge is used to scatter the sand gently on the sea floor and disturb buried fish. When a fish is spotted, the dolphin drops the sponge and gives chase. "It has been thought that behaviours which are exclusively learnt from one parent are not very stable. With our model we could now show that sponging can be a stable behaviour," said Dr Anna Kopps, a biologist at the University of New South Wales.

Read the given passage carefully and answer the following question.

In 1984, researchers spotted dolphins doing something broken in Shark Bay, Western Australia. When the animals got hungry, they ripped a marine basket sponge from the sea floor and fitted it over their beaks like a person would fit a glove in a hand. The scientists suspected that as the dolphins foraged for fish, the sponges protected their beaks, or rostra, from the rocks and acoustic chunks of coral that litter the sea floor, making this behaviour the first example of tool use in this species.

The researchers surmised that a long time ago one ingenious Shark Bay dolphin figured out that by prodding the sediments with a sponge attached to her beak, she could stir up these swim bladder-less fish without being hurt. Eventually, such a technique became apparent among other dolphins. But why do dolphins go through all of this trouble when they could simply snag a fish from the open sea? The answer is that the bottom-dwelling fish are a lot more nutritious.

Some species also don't have swim bladders or gas chambers that help other fish control their buoyancy as they travel up and down the water column. In the Bahamas, where dolphins are also known to forage for bottom-dwelling fish, dolphins hunt partly by echolocating these bladders, which give off a strong popular signal. That helps the cetaceans find prey even when it's buried in sea sand. But bottom-dwelling fish, such as Barred Sandperch, which are favoured by some Shark Bay dolphins, don't have swim bladders and so are harder to find with echolocation. The sea floor is not nearly as soft here as it is in the Bahamas, so if dolphins want to probe for these fish, they risk injuring their rostra.

Not every dolphin in Shark Bay hunts with sponges. "It's primarily done by females," says Janet Mann, a behavioural ecologist. She believes the female dolphins invented the method because of the "selective pressures they face while raising a calf as long as they do," about 4 to 5 years. "These clever dolphins have figured out a way to target fish that other dolphins cannot," she says, adding that even the local fishermen do not catch, or even know about, this particular species. Mann's previous research has shown that dolphin mothers pass the sponging method to their daughters and some of their sons, rare evidence of a cultural tradition in an animal other than humans. The team has documented three generations of sponging dolphins.

The foraging technique came to light a few decades ago - very recently in evolutionary terms - when a local fisherman spotted what looked like a strange tumour on a dolphin’s nose. Researchers eventually worked out that the ‘tumour’ was a conically shaped sponge and it became unusual that the dolphins would spend considerable time searching for one the right shape to fit their nose. The sponge is used to scatter the sand gently on the sea floor and disturb buried fish. When a fish is spotted, the dolphin drops the sponge and gives chase. "It has been thought that behaviours which are exclusively learnt from one parent are not very stable. With our model we could now show that sponging can be a stable behaviour," said Dr Anna Kopps, a biologist at the University of New South Wales.