How parrots mimic human speech, new study


This video is called Parrots: Majestic Birds (Nature Documentary).

From Wildlife Extra:

Scientists solve how parrots mimic humans

Ever wondered how parrots are ablie to mimic human speech? New research indicates that it is key structural differences in the brains of parrots that explain a parrot’s unparalleled ability to imitate sounds and human speech. This research was led by an international team of scientists led by Duke University researchers.

“This finding opens up a huge avenue of research in parrots, in trying to understand how parrots are processing the information necessary to copy novel sounds and what are the mechanisms that underlie imitation of human speech sounds,’ said Mukta Chakraborty, a post-doctoral researcher in the lab of Erich Jarvis, an associate professor of neurobiology at Duke and a Howard Hughes Medical Institute Investigator.

Parrots are one of the few animals considered ‘vocal learners,’ meaning they can imitate sounds, and researchers have been trying to figure out why some bird species are better imitators than others. Besides differences in the sizes of particular brain regions, however, no other potential explanations have surfaced.

By examining gene expression patterns, the new study found that parrot brains are structured differently than the brains of songbirds and hummingbirds, which also exhibit vocal learning. In addition to having defined centres in the brain that control vocal learning called ‘cores,’ parrots have what the scientists call ‘shells,’ or outer rings, which are also involved in vocal learning.

The shells are relatively bigger in species of parrots that are well known for their ability to imitate human speech, the group found.

Until now, the budgerigar (common pet parakeet) was the only species of parrot whose brain had been probed for the mechanisms of vocal learning.

This team included researchers from Denmark and the Netherlands who donated precious brain tissue for the study. They characterized the brains of eight parrot species besides the budgerigar, including conures, cockatiels, lovebirds, two species of Amazon parrots, a blue and gold macaw, a kea and an African Grey parrot.

The researchers looked for specific gene markers that are known to have specialized activity in the brains of humans and song-learning birds.

They compared the resulting gene expression patterns in all the parrot brains with neural tracing experiments in budgerigars.

Even the most ancient of the parrot species they studied, the Kea of New Zealand, has a shell structure — albeit rudimentary. This suggests that the populations of neurons in the shells probably arose at least 29 million years ago.

Before now, some scientists had assumed that the regions surrounding the cores had nothing to do with vocal learning. In a 2000 study, Jarvis and Claudio Mello of Oregon Health & Science University concluded that the core and shell were actually one large structure. These differing views caused confusion about the sizes of the brain regions important for vocal learning. Jarvis teamed up with Steven Brauth from the University of Maryland and his former postdoctoral fellow Sarah Durand, to help reconcile this confusion.

‘The first thing that surprised me when Mukta and I were looking at the new results is, ‘Wow, how did I miss this all these years? How did everybody else miss this all these years?” said Jarvis, who is also member of the Duke Institute for Brain Sciences. ‘The surprise to me was more about human psychology and what we look for and how biased we are in what we look for. Once you see it, it’s obvious. I have these brain sections from 15 years ago, and now I can see it.’

The new results support the group’s hypothesis that in humans and other song-learning animals, the ability to imitate arose by brain pathway duplication. How such a copy-and-paste job could have happened is still unknown.

‘How can you get a mirrored song system surrounding another one?’ Jarvis asks. ‘Each (vocal learning centre) has a core and a shell in the parrot, suggesting that the whole pathway has been duplicated.’

Most of the bird’s vocal learning brain regions are tucked into areas that also control movement. These areas in parrots also show some special patterns of gene expression, which the scientists speculate might explain why some parrots are also able to learn to dance to music.

‘It takes significant brain power to process auditory information and produce the movements necessary for mimicking sounds of another species,’ Chakraborty said. ‘The question is, how specialized are these parrot brains, and in what ways? Is it just a select group of specialized genes, or is it some specific projections that we haven’t discovered yet?’

The scientists are especially curious about whether the shells give parrots a greater ability to imitate human speech.

‘If that’s true, then we’ve answered a big question in our field that people have been wanting to know for many years,’ Jarvis said.

Australian parrots’ beaks and global warming


This video is called Mulga parrot – Bird watching in Australia.

From Wildlife Extra:

Bigger beaks help birds combat global warming

To help them cope with climate change birds are grow[ing] bigger beaks, new research suggests. The scientists, led by Dr Matthew Symonds from Deakin’s Centre for Integrative Ecology in Australia, have discovered a pattern between increased climatic temperatures and an increase in the size of the beaks of parrot species in southern and eastern Australia.

“Birds use their beaks to keep themselves cool. Just as an elephant’s ears help to act as a fan to keep the animal cooler, birds can pump blood to their highly vascularized bills, enabling them to lose excess heat when they get hot,” Dr Symonds said.

The researchers examined 410 bird skins, collected between 1871 and 2008 and located at Museum Victoria, the Queensland Museum, the South Australian Museum and the Australian National Wildlife Collection, Canberra.

They found that four of the five species examined had measurably bigger beaks now than they had in the 19th century.

“In an earlier study we found that birds in hotter climates had bigger beaks than those in cooler climates, which prompted us to look at whether there has been an increase in beak size generally as the climate has got hotter over the past century,” Dr Symonds said.

“We found an increase in beak surface area of between four and 10 per cent, which may not sound like much, but would actually make a huge difference to the birds’ ability to cool down when they are stressed by heat. We have been able to show there has been an increase in the size of the beaks, in line with the increase in the temperature these parts of Australia have experienced over the same time frame.

“However, we can’t yet conclusively rule out the effect of other environmental factors, such as changes in habitat or food availability. This work provides an important basis on which to do more research. The next step will be to expand the research to consider a wider range of species from other regions, and with different kinds of beak shapes and lifestyles.

“Aside from it indicating another way in which climate change is affecting animals, the beak is so intimately tied to a birds’ lifestyle that climate-related changes in beaks may have further ramifications for other aspects of their biology: what kind of food they eat, how they compete with each other and how they reproduce.”

The five native Australian parrot species examined were the mulga parrot (Psephotus varius), gang-gang cockatoo (Callocephalon fimbriatum), red-rumped parrot (Psephotus haematonotus), Australian king parrot (Alisterus scapularis) and crimson rosella (Platycercus elegans). The Australian king parrot was the only species where an increase in beak size was not recorded.

The research, “Climate-related spatial and temporal variation in bill morphology over the past century in Australian parrots”, has been published in this month’s edition of the Journal of Biogeography</em>.

Lorikeets, originally from New Guinea?


This video from Australia says about itself:

Lorikeet Feeding Frenzy

22 November 2012

The feeding of the Rainbow Lorikeets at Bungalow Bay Koala Village which is on the North-east side of Magnetic island, just off the coast of Townsville, Queensland.

From Molecular Phylogenetics and Evolution, Volume 90, September 2015, Pages 34–48:

Molecular phylogenetics suggests a New Guinean origin and frequent episodes of founder-event speciation in the nectarivorous lories and lorikeets (Aves: Psittaciformes)

Highlights

We report the first DNA sequence-based phylogeny of parrots known as lories and lorikeets.

The group is inferred to have originated within the last 10 million years in New Guinea.

Dispersal and founder-event speciation have been important in their diversification.

Dispersal appears to have been primarily ‘downstream’ from New Guinea and Australia.

Some genus level changes to the group’s systematics are recommended.

Abstract

The lories and lorikeets (Aves: Loriinae: Loriini) are a readily recognizable, discrete group of nectarivorous parrots confined to the Indo-Pacific region between Wallace’s Line and the Pitcairn Island group in the central-east Pacific Ocean. We present the first phylogenetic analysis of all currently recognized genera in the group using two mitochondrial and five nuclear loci.

Our analyses suggest a New Guinean origin for the group at about 10 million years ago (95% HPD 4.8–14.8) but this origin must be interpreted within the context of that island’s complicated, recent geological history. That is, the origin and early diversification of the group may have taken place as New Guinea’s Central Cordillera arose and the final constituent terranes that form present-day New Guinea were accreted. The latter activity may have promoted dispersal as a key element in the group’s history.

We have detected several instances of dispersal out of New Guinea that we argue constitute instances of founder-event speciation. Some phenotypically cohesive genera are affirmed as monophyletic but other genera are clearly in need of taxonomic dismantlement and reclassification. We recognize Parvipsitta Mathews, 1916 for two species usually placed in Glossopsitta and we advocate transfer of Chalcopsitta cardinalis into Pseudeos Peters, 1935. Other non-monophyletic genera such as Charmosyna, Psitteuteles and, probably, Trichoglossus, require improved taxon sampling and further phylogenetic analysis before their systematics can be resolved. Cursory examination of trait mapping across the group suggests that many traits are ancestral and of little use in determining genus-level systematics.

Lorikeet and lori family tree, according to new research

Rose-ringed parakeets preparing to sleep


This video, by Luuk Punt from the Netherlands, is about rose-ringed parakeets, also called ring-necked parakeets, Psittacula krameri, gathering in trees in Leiderdorp, the Netherlands, to sleep, on 23 October 2011.

Recently, big groups of rose-ringed parakeets started sleeping in Leiderdorp. They sleep in a part of the town called Vogelbuurt, where streets have birds’ names.

This Leiderdorp parakeet video is the sequel to the first one.

Australian night parrot killed by feral cat


This video from Australia says about itself:

3 July 2013

Thought to be extinct: Queensland bird enthusiast presents first photos of the elusive night parrot.

From the Birds Alive Newsletter, March 2015:

Feral cats versus Night Parrots

The latest twist in the rather secret story of the Night Parrot (Pezoporus occidentalis) is that a cat-killed individual has been found in an area of arid spinifex country SW of Winton, in W Queensland, close to where John Young photographed the species for the first time in May 2013.

Apparently, according to Queensland government sources, professional marksmen have been employed by a private conservation company to patrol the area at night with spotlights, shooting feral cats (Felis catus) on sight. The programme is funded by mining company Fortescue Metals, whose involvement dates back to the reported discovery of Night Parrots in a mineral exploration area in Western Australia in 2005. However, government agencies have been kept in the dark concerning the whereabouts of Night Parrots in Queensland, and the sites where the species occur are on a privately leased grazing property.

Feral cats have long been implicated in the decline of this once widespread species: in 1892, it was reported that ‘numerous’ parrots were killed by cats near Alice Springs. Some observers have noted increases in feral cat populations in recent years in parts of inland Australia. The region around Winton where the parrots occur has been drought-afflicted for several years.

Endangered Puerto Rican parrots released into the wild


This video says about itself:

19 March 2014

Get to know the Puerto Rican Parrot with Mr. Wizard.

From La Prensa in Puerto Rico:

15 Endangered Puerto Rican parrots released into the wild

22 January 2015

San Juan, Jan 22 (EFE). Fifteen Puerto Rican parrots were released into the wild to strengthen the critically endangered species, the Department of Natural and Environmental Resources, or DRNA, said.

The release of the birds, also known as Puerto Rican amazons, in the Rio Abajo State Forest “is a crucial step in the program to restore this species,” DRNA Secretary Carmen Guerrero said.

“Each time we release birds, with the intention of increasing the number of parrots living in the wild, we advance step by step toward a not-so-distant future when the bird the Tainos (Puerto Rico‘s early inhabitants) called the iguaca may be taken off the list of species in danger of extinction,” she said.

The DRNA is in the process of preparing an additional 200 Puerto Rican to be released into the wild.

The most recent census found the number or Puerto Rican parrots living free in the Rio Abajo State Forest ranges between 50 and 100, with another group in the El Yunque National Park on the island’s northeastern coast.

The program to restore the species is led by DRNA, the U.S. Fish and Wildlife Service and the United States Forest Service.

Birds being trained for life in the wild must spend at least one year in cages large enough to allow flight. They are fed with fruits they will find in the wilderness and taught to recognize their natural predators.

Two Puerto Rican parrots were born in the wild last year in the Rio Abajo, an landmark achievement for the program.

Authorities estimate that Puerto Rico was home to more than 1 million Puerto Rican parrots in the 19th century. By the 1950s, their numbers had fallen to barely 200.

In 1968, the species was included in the U.S. federal endangered species list and the restoration program began in 1973 with a first center in El Yunque for reproduction in captivity.

A second center for reproduction in captivity was established in Rio Abajo in 1993.

The first release of a batch of Puerto Rican parrots took place in 2000 in El Yunque, followed in 2006 by a release in Rio Abajo.