Featured Research

from universities, journals, and other organizations

Understanding Algae That Are Both 'Plant' And 'Animal'

Date:
June 20, 2007
Source:
University Of Kalmar
Summary:
Nature is full of surprises. There are some algal species that can act both as "plants" and as "animals" at the same time. Why do these organisms have this behavior and what might be the effects of this nutrition on the environment, economy and public health issues?

Nature is full of surprises. There are some algal species that can act both as “plants” and as “animals” at the same time. Wanderson Carvalho from the University of Kalmar in Sweden has in his research for his PhD degree, contributed to better understand why these organisms have this behavior and what might be the effects of this nutrition on the environment, economy and public health issues.

Related Articles


We know that in terrestrial ecosystems, plants are the only living beings capable of producing their own food. This is only possible thanks to the chlorophyll and other pigments which can capture the sunlight energy.

With this energy and nutrients (e. g. nitrogen and phosphorus) from land and carbon dioxide from the atmosphere they produce organic material. Plants are thus producers and belong to the base of the food chain. Until recently it was believed that the same system worked for lakes and the sea, where phytoplankton (microalgae) served as food for zooplankton (microscopic animals), which in turns were eaten by small fishes, which were eaten by bigger fishes and then by humans and other top predators. However, nature is full of surprises! There are algae species that can act both as “plants” and as “animals” at the same time.

As “plants” the algae produce their own food and as “animals” they can eat other plants or even their own grazers. These organisms are called mixotrophs and their nutritional strategy is thus known as mixotrophy, in other words: “mixed nutrition”. This dual nutritional behavior affects the notion of food chain mentioned above. In a comparison, imagine if instead of a cow eating the grass, the grass grabs and eats the cow.

The thesis of Wanderson Carvalho had as one of the objectives to quantify in two mixotrophic species how much nitrogen and phosphorus are needed when they act as “plants” and as “animals”, respectively. For example, under nutrient (nitrogen and phosphorus) deficient conditions, mixotrophs can outcompete other algae species by eating them or utilizing the little available nutrients dissolved in the water. Wanderson also found out that “feeding as animals” can also provide carbon and energy to the mixotrophs if light is low or absent.

In absence of food, mixotrophs can use their photosynthetic capabilities to survive until suitable prey is available again. Mixotrophs can decrease competition since they can feed on their competitors and predators alike. Mixotrophs can survive adverse periods and because of that many mixotrophs form blooms, becoming potentially harmful to the environment.

Wanderson Carvalho thesis is entitled "The Role of Mixotrophy in the Ecology of Marine 'Phytoplankton.'"


Story Source:

The above story is based on materials provided by University Of Kalmar. Note: Materials may be edited for content and length.


Cite This Page:

University Of Kalmar. "Understanding Algae That Are Both 'Plant' And 'Animal'." ScienceDaily. ScienceDaily, 20 June 2007. <www.sciencedaily.com/releases/2007/06/070619182508.htm>.
University Of Kalmar. (2007, June 20). Understanding Algae That Are Both 'Plant' And 'Animal'. ScienceDaily. Retrieved October 25, 2014 from www.sciencedaily.com/releases/2007/06/070619182508.htm
University Of Kalmar. "Understanding Algae That Are Both 'Plant' And 'Animal'." ScienceDaily. www.sciencedaily.com/releases/2007/06/070619182508.htm (accessed October 25, 2014).

Share This



More Plants & Animals News

Saturday, October 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Reuters - Innovations Video Online (Oct. 24, 2014) Miniature deep sea animals discovered off the Australian coast almost three decades ago are puzzling scientists, who say the organisms have proved impossible to categorise. Academics at the Natural History of Denmark have appealed to the world scientific community for help, saying that further information on Dendrogramma enigmatica and Dendrogramma discoides could answer key evolutionary questions. Jim Drury has more. Video provided by Reuters
Powered by NewsLook.com
Black Bear Cub Goes Sunday Shopping

Black Bear Cub Goes Sunday Shopping

Reuters - Light News Video Online (Oct. 23, 2014) Price check on honey? Bear cub startles Oregon drugstore shoppers. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Dances With Wolves in China's Wild West

Dances With Wolves in China's Wild West

AFP (Oct. 23, 2014) One man is on a mission to boost the population of wolves in China's violence-wracked far west. The animal - symbol of the Uighur minority there - is under threat with a massive human resettlement program in the region. Duration: 00:41 Video provided by AFP
Powered by NewsLook.com
Breakfast Debate: To Eat Or Not To Eat?

Breakfast Debate: To Eat Or Not To Eat?

Newsy (Oct. 23, 2014) Conflicting studies published in the same week re-ignited the debate over whether we should be eating breakfast. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins