Difference between revisions of "Foraminifera feeding on diatoms"
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| − | The study carried out by Austin et al (2005) provides the first direct observational link between the fracturing of diatom frustules and active feeding/sequestration mechanisms in benthic foraminifera. Chemical fixation and subsequent scanning electron microscopy (SEM) suggest the active transportation of diatoms and use of the tubercles in H. germanica to crack/fracture diatom frustules in a characteristic manner which may allow recognition of benthic foraminiferal feeding/sequestration activity. | + | The study carried out by Austin et al (2005) provides the first direct observational link between the fracturing of diatom frustules and active feeding/sequestration mechanisms in benthic foraminifera. Chemical fixation and subsequent scanning electron microscopy (SEM) suggest the active transportation of diatoms and use of the tubercles in ''H. germanica'' to crack/fracture diatom frustules in a characteristic manner which may allow recognition of benthic foraminiferal feeding/sequestration activity. |
The forces required to induce such a cracking effect are likely to be large. For example, a study carried out by Hamm et al. (2003), where the pennate planktonic diatom ''Fragilariopsis kerguelensis'' was studied, demonstrated cracking when an experimental force of 750 AN was applied. The processes controlling silicification in both planktonic and benthic diatoms are known to vary according to a number of factors (see Raven and Waite, 2004 for a review) and it can be speculated that similar or even greater forces are required to crack the large, benthic species ''P. angulatum''. Interestingly, Hamm et al. (2003) speculated because of the very large forces required to break diatom frustules, that grazers are likely to have evolved specialised tools to break open diatoms. | The forces required to induce such a cracking effect are likely to be large. For example, a study carried out by Hamm et al. (2003), where the pennate planktonic diatom ''Fragilariopsis kerguelensis'' was studied, demonstrated cracking when an experimental force of 750 AN was applied. The processes controlling silicification in both planktonic and benthic diatoms are known to vary according to a number of factors (see Raven and Waite, 2004 for a review) and it can be speculated that similar or even greater forces are required to crack the large, benthic species ''P. angulatum''. Interestingly, Hamm et al. (2003) speculated because of the very large forces required to break diatom frustules, that grazers are likely to have evolved specialised tools to break open diatoms. | ||
