АкушерствоАнатомияАнестезиологияВакцинопрофилактикаВалеологияВетеринарияГигиенаЗаболеванияИммунологияКардиологияНеврологияНефрологияОнкологияОториноларингологияОфтальмологияПаразитологияПедиатрияПервая помощьПсихиатрияПульмонологияРеанимацияРевматологияСтоматологияТерапияТоксикологияТравматологияУрологияФармакологияФармацевтикаФизиотерапияФтизиатрияХирургияЭндокринологияЭпидемиология

The Song of the Love-Lorn Whale

"Ditties" sung by humpback whales, possibly the most complicated songs in the animal kingdom, are really "operas". And even more remarkable, these operas vary from one ocean basin to another. Over the past 4 years, a team of scientists led by H. E. Winn, travelled the Atlantic and Pacific Oceans to hear these "dialects".

Early recordings made in high latitudes, where a humpback spends the summer months feeding on tiny Crustacea, indicated a rather limited vocal performance consisting of "wheezing blows" and fast "clicks". Scientists thought these were used for exploring the local terrain by echolocation.

However, later recordings made in 1971 off Bermuda during the calving season revealed the winter songs to be a more complicated, ordered sequence of sounds lasting from 6 to 30 minutes. Winn's team was surprised to see the pattern of sounds repeated over and over again.

The song is composed of a great variety of sounds - from low "ele­phant snores" through moans, groans, "wavery oohs" and "long yups" to chirps, cries and the "surface ratchet" which the whale "sings" immediately before surfacing. All the songs heard in one locality closely resemble one another, and up to 18 different sounds may occur in the song, linked together into short rhythmical phrases. A number of these phrases are repeated in a certain sequence or theme. The singer then progresses in an orderly fashion through several themes, before surfacing briefly for a breath of air for another rendering.

In this latest study careful comparisons were made between the spectrographs of songs recorded in the Cape Verde Islands, off Africa in the North Atlantic, and those from the West Indies, 4300 km away.

Despite some minor differences the song formats were essentially the same. Similarly, in the North Pacific songs from Hawaii and Mex­ico, (5000 km distant) were nearly identical, though very different from the North Atlantic songs. Songs recorded off Tonga in the South Pacific (where whales migrate 6 months out off phase with those in the northern hemisphere) were unlike either of these types.

The singers are probably unpaired males, and it seems likely that the song serves some function in courtship. The hearing of a whale is believed to be acute, and the songs may be heard tens or even hundreds of kilometres away, allowing the singers to advertise their suitability and desirability to potential mates and rivals over a wide 40 area. Females may assess the suitability of future mates on the basis of a song's intricacy. Scientists have noticed that performance of some Herculean task during courtship is expected in species where a couple stays together for a long time - and the same pairs of hump­backs have been sighted year after year. The song could also be used 45 to identify particular whales, as individual peculiarities have been detected. It remains to be seen whether the isolation of whales in dif­ferent parts of the world's oceans means that genetic differences underlie the song dialects, or whether this is a purely cultural phenom­enon based on learned traditions.

1. Skimming

Read through the passage very quickly. Do not try to understand every word; just try to get a general idea. Now choose a new title for the passage, from this list:

(a) Why whales sing

(b) The song of the humpback whale

(c) A study in animal communication

(d) Whales of the North Atlantic

(e) Animal radar

2. Understanding in detail

Choose the correct answer, according to what you have read in the text

(a) How does a single male whale probably communicate with a suitable mate?

(i) by singing a complicated song

(ii) by fighting with rival males

(iii) by swimming hundreds of kilometres

(b) What is the highest number of sounds heard in one whale "song"?

(i) thirty

(ii) six

(iii) eighteen

(c) How might an individual whale be identified?

(i) by the area in which it lives

(ii) by the song it sings

(iii) by the distance it swims

(d) In which season of the year can North Atlantic whales be seen off Bermuda?

(i) summer

(ii) winter

(e) What was discovered about the songs of whales in one lo­cality?

(i) They all had eighteen sounds in them

(ii) They were all very similar to each other.

3. Find in the text the following words and expressions and translate them into Russian