HOME >> BIOLOGY >> NEWS
Getting an evolutionary handle on life after reproduction

Since many animals live beyond their fertile years, biologists have searched for evolutionary clues to this extended lifespan. What role, if any, does natural selection play in the evolution of the postreproductive lifespan? For natural selection to shape the twilight years, postreproductive females should contribute to the fitness of their offspring or relatives, a hypothesis called the "grandmother effect." Though many mammals, including lions and baboons, rear dependent young and operate within complex social groups, studies have found no evidence of a granny effect, and females mostly live just long enough to care for their last born. For nonsocial animals that spawn independent young, extended lifespan is associated with good nutrition and the absence of disease and predators.

In a new study, David Reznick, Michael Bryant, and Donna Holmes provide the first experimental confirmation that evolution works selectively on those aspects of life history that directly affect fitness. They expand on their ongoing investigations of the life history of guppies confronting different predatory threats in Trinidad. Individuals facing different mortality threats should evolve different adaptations in their life histories, such as age at first reproduction, investment in reproduction, and patterns of senescence, including declines in reproduction. Since guppies are livebearers that provide no postnatal maternal care, Reznick et al. predicted the populations would show no differences in postreproductive lifespan--which is what they found.

Though overall lifespan varied among the populations, these variations stemmed from differences in time allotted only to reproduction. Postreproductive lifespan, in contrast, showed no signs of being under selection, and appeared to be what the authors called a "random add-on at the end of the life history." Random or not, this is the first demonstration of a postreproductive lifespan in fish.

These findings
'"/>

Contact: Paul Ocampo
press@plos.org
415-624-1224
Public Library of Science
26-Dec-2005


Page: 1 2

Related biology news :

1. Getting to the root of plant growth
2. Getting to the core of an emergent public health threat
3. Getting dirty may lift your mood
4. Getting on your nerves ... and repairing them
5. Getting ones protein in a bunch -- When quality control fails in cells
6. Getting to the bottom of memory
7. Getting to the heart of the heart
8. Getting America really ready
9. Getting ahead of cancer: SPECT/Spiral CT technology enhances bone scanning, earlier diagnosis
10. Getting ACL tears to heal themselves
11. Getting old? Slowing down? Blame inefficient mitochondria

Post Your Comments:
*Name:
*Comment:
*Email:
TAG: Getting evolutionary handle life after reproduction

(Date:4/13/2015)...  higi, a leading cloud-based consumer engagement platform that ... with their communities around health and wellness, announced today ... API.  ... and convenient vehicle to receive validated health information from ... The API will allow higi,s trusted partners, on a ...
(Date:4/8/2015)...  Infinisource, a leading provider of SaaS-based Human Capital ... leading supplier of biometric identification and security solutions, ... advanced biometrically-enabled time clock, the companies announced today. ... setting a bold, new standard for the collection ... and mid-size employer. When connected to the iSolved ...
(Date:4/2/2015)... Md. , April 2, 2015 At ... Salt Lake City , the American College ... of five new directors to its Board.  Members of ... the ACMG and for forming and advancing its policies ... medical genetics profession. "It,s an eventful time ...
Breaking Biology News(10 mins):higi Launches Seamless Access to HIPAA-Compliant Health Outcomes and Activity Data 2higi Launches Seamless Access to HIPAA-Compliant Health Outcomes and Activity Data 3iSolved Time Clock Offers Unmatched Accuracy due to Morpho Biometrics 2iSolved Time Clock Offers Unmatched Accuracy due to Morpho Biometrics 3American College of Medical Genetics and Genomics Announces New Board Members: Dr. Louanne Hudgins is ACMG President-Elect 2American College of Medical Genetics and Genomics Announces New Board Members: Dr. Louanne Hudgins is ACMG President-Elect 3American College of Medical Genetics and Genomics Announces New Board Members: Dr. Louanne Hudgins is ACMG President-Elect 4American College of Medical Genetics and Genomics Announces New Board Members: Dr. Louanne Hudgins is ACMG President-Elect 5American College of Medical Genetics and Genomics Announces New Board Members: Dr. Louanne Hudgins is ACMG President-Elect 6American College of Medical Genetics and Genomics Announces New Board Members: Dr. Louanne Hudgins is ACMG President-Elect 7American College of Medical Genetics and Genomics Announces New Board Members: Dr. Louanne Hudgins is ACMG President-Elect 8
(Date:4/25/2015)... WI (PRWEB) April 25, 2015 Join ... April 29th: Analyzing Kinase Inhibitor Residence Times using the ... Analysis of inhibitor residence times is increasingly being incorporated ... target can result in improved efficacy, increased therapeutic window ... be determined using immobilized ligand methods such surface plasmon ...
(Date:4/24/2015)... (PRWEB) April 24, 2015 Top student ... other San Diego area universities, including UCSD and SDSU, ... judges from prominent local, national and nonprofit companies for ... the 5th Annual Social Innovation Challenge 2015 . ... unique social venture ideas addressing a diverse range of ...
(Date:4/24/2015)... SD and Tempe, AZ (PRWEB) April 24, 2015 ... Technology and Arizona State University (ASU) have entered into ... joint projects. , A memorandum of agreement signed by ... long distance learning, student success and other services particularly, ... resources. , “We have complementary strengths and a ...
(Date:4/24/2015)... Leading Regenerative Veterinary Medicine company ... stem-cell product development program and changes its’ name ... strategic direction. , “I am extremely pleased to ... development program has been kicked into high gear ... and hiring of our new Director of Research ...
Breaking Biology Technology:BellBrook Labs Webinar: Analyzing Kinase Inhibitor Residence Times using the Transcreener® ADP Assay 25th Annual Social Innovation Challenge at University of San Diego - Students Pitch to Live Judging Panel to Take Home $75K 25th Annual Social Innovation Challenge at University of San Diego - Students Pitch to Live Judging Panel to Take Home $75K 3South Dakota Mines, Arizona State University Pave Way for Cooperative Research 2Vet-Stem, Inc. Meets New Milestones and Changes Name to VetStem Biopharma 2
Cached News: